Retailer EDI orders error out and someone re-keys them. It is usually a cross-reference problem, not an EDI problem. In one case the rows predated the customer's pack-size change. We repointed them and verified on live orders. We work in SPS Commerce regularly.
Inventory lives at a 3PL or co-packer and the counts never match. We reconcile the 3PL's record to Acumatica, find the duplicate items and orphaned allocations, and specify the integration so it stays matched.
Landed cost never reaches item cost, so margin is wrong. Often one release setting. We clear the backlog and tie out the accrual account.
Nobody can see revenue, deductions and cost by customer. We build it from native inquiries first, then Velixo or Power BI where it earns its place. Chargebacks and promotional deductions get their own reason codes so they stop hiding in credit memos.
Lot and expiry are tracked on paper. Lot-tracked items, first-expired picking and a recall trace that runs in minutes.
Channels do not reconcile. Shopify and Amazon payouts that nobody can tie to orders. We build the reconciliation so month-end is routine.
Units of measure fight each other. Each, inner, case and pallet, set up once and tested against real receipts and real EDI orders.