Mistakes 1 and 2: Shared size bins and visual-only checks
Storing every size of a style in one bin is the most common cause of wrong-size shipments. Pickers grab the closest polybag, glance at a small size sticker and move on. Small versus medium, or black versus washed black, is an easy miss at speed, and the customer finds out before you do.
The second mistake compounds the first: relying on a visual check instead of a scan. Human eyes are good at spotting a red shirt in a blue order. They are bad at spotting a 30-inch inseam in a 32-inch order.
The fix for both is straightforward. Give each variant a dedicated or clearly divided location, and scan every unit against the order line at pick and again at pack. Slow fringe sizes can share space with dividers, but each one needs its own identifiable spot and barcode.
Mistake 3: Sending inventory with bad or missing barcodes
Inventory that arrives with no barcode, duplicate barcodes across sizes, or a factory code that does not match your storefront SKU slows receiving and creates errors that can last for months.
It usually starts at the factory. A supplier reuses a barcode across colorways, prints the size label on the carton but not the polybag, or uses an internal style number instead of your UPC. Every one of those units has to be identified by hand and relabeled before it can be put away.
Send your factory a barcode and labeling spec before production, ask for a pre-shipment photo of finished units, and budget for relabeling when something slips through. It is far cheaper than shipping the wrong size.
Mistakes 4 and 5: Slow returns and skipped refurbishment
Returns left unprocessed for a week or more cost money twice: the units cannot be resold, and your storefront may show popular sizes as out of stock while they sit in a cage. In apparel, where full-price selling windows are short, that delay can push good product into markdown.
Aim for daily returns processing with clear, written grading rules so every inspector makes the same call.
The related mistake is skipping refurbishment. Many returned garments are only a steam, a fresh fold, a new polybag or a replacement hangtag away from full price. Brands that skip that step send resellable product to outlet or liquidation channels unnecessarily. Decide which refurbishment steps are worth the cost for each product family, then make them part of the standard returns flow.
Mistake 6: Using one package for everything
One-size-fits-all packaging drives up shipping costs and can damage structured garments. A single T-shirt in a large box may be billed on dimensional weight, while a tailored jacket squeezed into a mailer arrives creased.
Match packaging to the product: poly or paper mailers for soft goods, right-sized boxes for structured pieces and larger multi-item orders. Keep a small, deliberate range of sizes rather than one default, and record packed dimensions per SKU so the right package is suggested automatically at the pack station.
Mistake 7: Treating drops like ordinary days
A product drop can compress a week of orders into an hour. Without staged inventory, pre-kitted bundles, extra pack labor and scheduled carrier pickups, orders back up, ship dates slip and customers post about it.
Share your launch calendar with your 3PL well ahead of time, including expected quantities by size, any bundles or limited packaging, and the date the release goes live. Confirm oversell protection on the storefront, and agree on how orders will be prioritized in the first hours.
Mistake 8: Ignoring the size curve
Ordering and stocking every size in equal quantities almost guarantees stockouts in core sizes and overstock in fringe sizes. A balanced-looking purchase order is often an unbalanced one in practice.
Use your own sales history by size, and by color where it differs, to set purchase quantities and channel allocations. Your fulfillment data helps here. Return reasons, exchange patterns and sell-through by variant show which sizes run small or large, which fits generate the most exchanges and which colors underperform. Feed that back into the next buy.
Mistakes 9 and 10: Underestimating wholesale and ignoring data
Many apparel brands treat their first big retail order like a large DTC order. Retailers expect specific EDI documents, GS1-128 carton labels, prepacks, hangers, ticketing and routing compliance. Missing any of these can lead to chargebacks that eat into an already thin wholesale margin. Before accepting a retail program, read the vendor guide end to end and confirm your 3PL can meet it, then run test shipments where the retailer offers them.
The final mistake is never looking at fulfillment data. Review a few metrics monthly: wrong-item complaints, return reasons by style, return processing time, inventory variances and shipping cost per order. Look for patterns rather than single incidents, such as one style driving most fit complaints or one package driving up cost.
How to audit your current setup
A quick audit covers all ten mistakes in an afternoon. Walk through each step of your fulfillment process and ask:
- Does each size and color have its own location and barcode?
- Is every unit scanned at pick and at pack?
- Do inbound units arrive with barcodes that match your storefront SKUs?
- How long do returns sit before processing, and what happens to Grade B items?
- Does packaging match the product, or is one box used for everything?
- Is there a written plan for the next drop?
- Are purchase quantities based on your own size curve?
- Could you meet a retailer's vendor guide today?
- When did you last review fulfillment metrics?
Any answer that starts with "it depends" is a place to focus first.
Frequently asked questions
What is the most common apparel fulfillment mistake?
The most common apparel fulfillment mistake is storing multiple sizes or colors together without scan verification, which leads to wrong-size and wrong-color shipments.
How fast should apparel returns be processed?
Apparel returns should ideally be processed daily, so units that pass inspection go back into sellable stock while they can still sell at full price.
How do I know if my 3PL is right for apparel?
A 3PL is a good fit for apparel if it controls inventory by variant, scans every unit, processes returns quickly, plans for drops and can meet retail EDI requirements.