Cut Picker Travel Now: A Manager's Pick Path Optimization Playbook

Manager's playbook linking routing algorithms, slotting, pilots, and orchestration to cut picker travel, boost picks/hour, and lower labor cost.

Pick path optimization cuts picker travel, raises picks per hour, and lowers labor cost per order. The fastest gains come from four levers working together: smarter slotting and layout, the right picking strategy for your order profile, an algorithm suited to your floor’s contention level, and a WMS or orchestration layer that can act on all three in real time. Start by measuring your baseline, then running a scoped pilot before touching the whole floor.

TL;DR:

  • Measuring travel distance and time per pick, along with accuracy, reveals where inefficiencies are most concentrated in specific zones and shifts.
  • Batch picking strategies generally outperform single-order picking for high SKU overlap and small order sizes, reducing travel time and congestion.
  • Hybrid heuristic routing algorithms that account for congestion outperform greedy shortest-path methods, especially during peak picker contention.
  • Implementing real-time control systems with live layout, congestion data, and dynamic routing enables continuous optimization instead of static plans.
  • Regularly reviewing KPIs like travel distance, picks per hour, and error rates prevents efficiency gains from slipping away over time.
  • Table of Contents

  • What Is Pick Path Optimization and Why Does It Matter?
  • How Do You Measure Your Current Pick Path Performance?
  • Which Picking Strategy Fits Your Order Profile?
  • Which Routing Algorithms Actually Work on the Warehouse Floor?
  • What WMS Features and Hardware Actually Enable Optimization?
  • How Does Warehouse Layout Change Your Pick Path Results?
  • How Do You Pilot and Roll Out Pick Path Changes?
  • How Do Orchestration Platforms Automate Pick Path Decisions?
  • What Should You Track After the Rollout to Keep the Gains?
  • The Gap Between Pick Path Theory and Warehouse Reality
  • A Faster Path to Fewer Wasted Steps on the Floor
  • Sources
  • What Is Pick Path Optimization and Why Does It Matter?

    Pick path optimization is the practice of determining the shortest, fastest, or most efficient sequence a picker or vehicle should travel through a warehouse to collect a list of items. It sounds simple until you watch a picker zigzag across six aisles to grab four SKUs that could have been collected in one loop. That waste compounds across every shift, every day, every peak season.

    The scale of the problem is the real story here. Industry estimates suggest travel eats up roughly 70% of a picker’s total working time, leaving only a fraction of the shift for the actual work of picking, scanning, and packing. That single number explains why most productivity gains in a distribution center come from moving people less, not moving them faster.

    A picker who saves even 90 seconds per pick run compounds into hours of reclaimed labor across a shift. That’s the arithmetic behind every pick-path initiative worth running.

    Better pathing translates directly into measurable outcomes:

  • Fewer travel minutes per order, which raises picks per hour without adding headcount
  • Lower cost per order, since labor is typically the largest controllable warehouse expense
  • Reduced congestion in high-traffic aisles during peak windows
  • Fewer picking errors, because shorter, simpler paths reduce cognitive load on pickers
  • None of this requires new robots or a rebuilt facility. It requires knowing where the travel is happening and why.

    How Do You Measure Your Current Pick Path Performance?

    You cannot optimize what you have not measured. Before changing a single aisle or algorithm, capture a baseline that tells you exactly where time and distance are going today.

    Four KPIs matter most:

  • Time per pick: average seconds from arrival at a slot to item collection, isolated from travel time
  • Travel distance per order: total feet or meters walked to complete an order, ideally pulled from cart odometry or RTLS tags
  • Picks per hour: the throughput number that ties directly to labor cost
  • Error rate: mis-picks per thousand lines, since a faster path that increases mistakes is not a win
  • Data sources for this baseline are usually already sitting in your systems:

    Once you have numbers, slice them by ABC velocity class, by zone, and by shift. A layout that performs well on day shift with slow-moving SKUs can look completely different during a night shift picking fast movers. The averages hide the problem; the slices reveal it.

    Which Picking Strategy Fits Your Order Profile?

    The strategy you assign to a shift changes the shape of every pick path that follows. Choosing the wrong one is the most common reason pathing efforts stall before they start.

  • Single-order picking: one picker completes one order start to finish. Simple to manage, but travel-heavy when order lines are scattered across the floor. Best for large or urgent orders where mixing SKUs risks errors.
  • Batch picking: a picker collects for multiple orders in a single pass, splitting items at a sort station afterward. This is where pick path optimization pays off fastest, since grouping orders that share SKU locations directly shortens the route.
  • Zone picking: pickers stay within a fixed zone and pass totes along a chain. Reduces travel per picker dramatically but demands tight handoff coordination and WMS support for zone routing.
  • Wave picking: orders release in scheduled batches tied to shipping cutoffs or labor shifts. This layers on top of batch or zone picking rather than replacing it, and it requires accurate demand forecasting to avoid bottlenecks.
  • The trade-off is consistent across all four: strategies that shrink individual travel distance (zone, batch) demand more WMS coordination and more complex task interleaving. Strategies that are operationally simple (single-order) leave the most travel time on the table.

    Pro Tip: If your order profile is mostly small, multi-line orders with high SKU overlap, batch picking will almost always beat single-order picking on travel time, even before you touch the routing algorithm.

    Which Routing Algorithms Actually Work on the Warehouse Floor?

    Pick path routing is, mathematically, a shortest-path or traveling salesman problem, and that framing matters because it tells you which algorithm fits which situation. Dijkstra’s algorithm and A* excel at finding the shortest route between two fixed points, which is useful for single-stop tasks like directing a picker to one slot. The moment an order has multiple stops, you’re in traveling salesman territory, and exact TSP solutions become computationally impractical once you’re routing dozens of stops across thousands of daily orders.

    That’s why real warehouse systems lean on heuristics instead of exact solutions:

  • S-shape (serpentine) routing: the picker sweeps each aisle end to end in sequence, simple to execute and easy for staff to learn
  • Largest-gap heuristic: skips the largest unused stretch of an aisle rather than walking it fully, cutting wasted distance in sparsely populated aisles
  • Nearest-neighbor: always moves to the closest unvisited pick, fast to compute but prone to getting boxed into inefficient detours late in the route
  • Christofides algorithm: a more rigorous TSP approximation that guarantees a route within a bounded distance of optimal, useful for high-value or high-density zones where the extra computation is worth it
  • For warehouses running many pickers simultaneously through shared aisles, a pure greedy algorithm (always take the shortest next step) behaves like a local firefighter: it solves the immediate problem in front of it without seeing the larger fire building elsewhere. Under high contention, greedy routing can cause multiple pickers to converge on the same aisle at once.

    A simulation-based analysis of path selection under contention found that greedy strategies can create herd effects when many agents chase the same shortest option simultaneously, while tuned hybrid strategies that mix in occasional randomization produced measurably better efficiency and system stability.

    This is where metaheuristics like Ant Colony Optimization (ACO) or Genetic Algorithms (GA) earn their place. They don’t find one perfect route; they search a wide space of possible routes and converge on strong solutions that account for congestion, not just distance. An epsilon-greedy hybrid, borrowed from that same contention research, takes the shortest path most of the time but occasionally samples an alternative, which keeps pickers from herding into the same bottleneck during peak waves. Warehouses running dozens of pickers through shared zones during a wave release see this instability constantly, and it’s usually invisible until someone finally graphs aisle congestion by minute.

    What WMS Features and Hardware Actually Enable Optimization?

    An algorithm is only as useful as the system that can execute its decisions in real time. Your WMS needs specific capabilities before dynamic pick path optimization is possible at all, and bolting routing logic onto a system that lacks them produces plans nobody on the floor can actually follow.

    The core software requirements:

  • Dynamic routing: recalculating a picker’s path as new orders release or congestion appears, rather than locking in a static route at shift start
  • Task interleaving: assigning putaway, replenishment, and picking tasks to the same worker along one efficient path instead of three separate trips
  • API access to the layout graph: the system needs a live map of aisles, slots, and distances to compute anything beyond guesswork
  • Live congestion signals: knowing which aisles are currently occupied prevents the herd effect described above
  • On the hardware side, pick-to-light and put-to-light systems remove ambiguity about which slot is next, voice-directed picking keeps hands free and eyes up, and handheld scanners confirm accuracy at each stop. Real-time location systems (RTLS) add the positioning data that makes dynamic routing possible rather than theoretical.

    Pro Tip: Before shopping for new hardware, audit whether your current WMS even exposes an API for live layout and congestion data. Many mid-market systems have the routing intelligence locked behind a dashboard nobody built integration for.

    How Does Warehouse Layout Change Your Pick Path Results?

    Software can only route pickers through the aisles you give it. Layout and slotting decisions set the ceiling on how much any algorithm can achieve, and in many operations a modest slotting change unlocks more efficiency than a routing upgrade alone.

    The core levers:

  • ABC velocity slotting: your fastest-moving 20% of SKUs, which typically drive the majority of pick volume, belong closest to the pack-out or shipping point, not scattered by arbitrary category
  • Cluster and family-based slotting: items frequently ordered together (a phone case and a screen protector) should sit near each other, shrinking multi-line pick distances regardless of which routing algorithm runs on top
  • Aisle width and cross-aisle placement: cross-aisles let pickers cut between rows instead of walking full aisle lengths, and adding even one mid-aisle cross point can meaningfully shorten serpentine routes
  • Golden zone placement: high-frequency items at waist to shoulder height reduce pick time itself, not just travel time
  • Before committing to a full re-slot, run a small trial: move one high-velocity zone, measure the change in travel distance for that zone alone over a week, and compare against the untouched control zones. Layout changes are expensive to reverse, so validate on a corner of the floor before committing the whole facility.

    How Do You Pilot and Roll Out Pick Path Changes?

    A rollout that skips the pilot stage is the single most common way pick path projects fail, because managers scale a change before confirming it actually works under real conditions.

  • Scope the pilot narrowly: pick one zone, one shift, or one order type rather than the entire facility, and hold a comparable control zone unchanged for comparison.
  • Write down your hypothesis before you start: state explicitly what you expect to change (for example, “batch picking cuts travel distance by 15% in the fast-mover zone”) so you know what success looks like.
  • Run the test long enough for statistical confidence: a single shift’s data is noise. Aim for at least two full weeks to smooth out day-to-day variation and shift differences.
  • Compare test and control on the same KPIs: time per pick, travel distance, picks per hour, and error rate, measured identically in both groups.
  • Build the rollout checklist before scaling: staff training on the new path logic, live dashboards for the new KPIs, and a documented fallback procedure if the new method underperforms during peak volume.
  • Pro Tip: Set a success gate before you start, not after you see the results. Decide in advance what improvement threshold justifies a full rollout, so a mediocre pilot doesn’t get talked into a facility-wide change out of sunk-cost pressure.

    Production-grade pick optimization tools that combine these heuristics with real operational constraints have reported cost reductions in the 15% to 30% range alongside service-level improvements, which gives you a rough benchmark for what a well-run pilot should be chasing.

    How Do Orchestration Platforms Automate Pick Path Decisions?

    Orchestration sits between your WMS and the floor itself, taking the routing, batching, and slotting logic covered above and turning it into live task assignments instead of static plans. Where a WMS tells you what needs to be picked, an orchestration layer decides who picks it, in what sequence, and through what path, updating continuously as conditions change.

    Lully operates at exactly this layer, integrating with existing WMS and ERP systems rather than replacing them.

    The practical case for orchestration over heavy robotics comes down to capital and flexibility:

  • No physical automation or conveyor infrastructure required, which means faster deployment and lower upfront cost
  • Adapts to workflow changes that would require reprogramming or re-engineering a fixed robotic system
  • Works across multi-building and multi-level facilities without site-specific hardware investment
  • For operations where the constraint is decision-making speed rather than physical throughput capacity, orchestration is often the higher-leverage investment.

    What Should You Track After the Rollout to Keep the Gains?

    Pick path gains erode quietly if nobody watches for it. Set a review cadence and know what backslide looks like before it costs you a quarter of throughput.

    Maintain a standing dashboard for the same four baseline KPIs, reviewed weekly at the operational level and monthly at the strategic level. Re-run your slotting or strategy analysis whenever SKU velocity shifts meaningfully, typically after a seasonal demand change or a new product line launch.

    Watch for these warning signs:

  • Model drift: routing that was optimal for last quarter’s SKU mix is quietly wrong for this quarter’s mix
  • Overfitting to averages: a route optimized for typical order size fails badly on outlier orders with unusual line counts
  • Ergonomic strain: shorter paths sometimes concentrate repetitive motion in ways that raise injury risk, which shows up in absenteeism before it shows up in the KPI dashboard
  • The Gap Between Pick Path Theory and Warehouse Reality

    Most advice on this topic treats algorithm choice as the whole story, and that’s backwards. The research on contention and herd effects makes clear that the smartest routing math in the world falls apart the moment you ignore what happens when forty pickers hit the same aisle during a wave release. Stability under load matters more than theoretical optimality, which is why a tuned hybrid heuristic consistently outperforms a “perfect” greedy algorithm on a busy floor.

    The other place conventional advice falls short is sequencing. Too many warehouses buy routing software before they’ve touched slotting, when the layout itself is often the cheaper, faster lever. A modest re-slot of your top velocity SKUs can outperform an algorithm upgrade, and it costs a fraction as much to test.

    If you take one thing from this, prioritize measurement before methodology. Get your baseline KPIs solid, pilot small, and only then decide whether the fix is a new picking strategy, a smarter algorithm, or a platform that can run those decisions continuously instead of once a quarter. Decision automation, the layer where platforms like Lully operate, matters most precisely because manual re-optimization can’t keep pace with a floor that changes every shift.

    — Michael

    A Faster Path to Fewer Wasted Steps on the Floor

    A practical alternative to a full robotics investment when your real bottleneck is decision speed, not physical capacity. Instead of ripping out your WMS or bolting on conveyors, Lully layers orchestration on top of what you already run, automating task assignment, batch and cluster pick routing, and workforce deployment in real time.

    That matters because everything covered above, from slotting to algorithm selection, requires someone or something recalculating decisions constantly as order mix and floor congestion shift. It fits multi-building and multi-level operations and adapts as workflows change, rather than locking you into a fixed routing scheme.

    If the baseline measurement and pilot design in this article surfaced gaps your current system can’t close on its own, see how Lully’s orchestration platform works and get a sense of what a pilot on your floor could look like.

    Sources

  • What is a Warehouse Pick Path? Optimization Guide & Tips — ShipBob
  • Pick-path optimization — Warehouse Science
  • An axiomatic analysis of path selection strategies for multipath transport (Keshvadi et al.)