What red flags should I watch for in a WMS demo?

The red flags most founders watch for are the ones visible from the buyer's seat: a vendor who can't answer a specific question, a feature that crashes mid-demo, a sales rep who doesn't know the product. Those are real signals. They're also the obvious ones — and obvious flags get caught by every founder, which means they rarely sort the good vendors from the bad ones in any decision-relevant way.

The flags that actually predict implementation problems are visible from the sell side, not the buy side.

A demo environment that walks through scenarios in a specific order, never deviating when asked to. Configuration changes that get demoed in a sandbox the vendor controls, never in a fresh environment. "We can customize that" as the answer to questions about gaps — every time, with no scope or cost framing attached. Rep handoffs to a solution architect who joins the demo, demos one piece flawlessly, then disappears for the rest of the engagement. None of these are visible-from-the-buyer-side problems. They look like normal, even polished, sales behavior — because they are normal sales behavior, calibrated to satisfy what buyers know to look for.

These patterns don't read as red flags from inside the buyer-only frame because the buyer has never sat on the other side. They read as flags to people who have watched what each pattern predicts in implementation: which deflection language signals a feature gap that will surface as a six-figure customization scope, which solution architect appearances predict an implementation team that won't include them, which sandbox demos paper over configuration limits the buyer would have caught in a fresh environment.

A founder watching for the wrong red flags in a polished demo will conclude the vendor passed. That conclusion is the predictable output of a process where the diligence is real but the frame is wrong.