Go and watch a shift before you write a line of code

A warehouse system was rejected in its second week. The functionality was correct, the interface had been user-tested, and the pilot team abandoned it within days.

The reason was that the scanner had to be held in the same hand as the scanner gun, and the confirmation button was in the bottom-right corner. Every confirmation required putting something down. Nobody in the project had held the device while doing the job.

What requirements documents never contain

Which hand is free. Almost never both. This one detail decides layout, target size and whether voice or scan input is worth building.

What the light is like. A screen tested at a desk is being tested in the best conditions it will ever see. Loading bays, cabs and outdoor sites are not those conditions.

How long people actually have. If the current way takes eleven seconds, a system taking fourteen will be abandoned regardless of how much better the data is afterwards. The comparison is always against the old way, not against nothing.

Where connectivity dies. Specifically: the far aisle, the lift, the yard, the basement. Not on average — in the exact places where the work happens.

What happens when somebody is interrupted. Constantly, in field work. A flow that loses state when a person walks away for ninety seconds will be worked around within a day.

Who they distrust and why. Field teams have usually been through a system that made their job harder and was withdrawn. That memory shapes the reception of yours, and it is worth knowing about before rather than after.

Two hours is usually enough

This does not require an ethnographic study. Stand where the work happens for one shift or part of one, and watch rather than ask.

Ask afterwards, and ask specifically: what is the most annoying part of this, what do you do when the system is wrong, what do you write on paper because it is faster. That last question reliably finds the real requirement, because paper survives only where it genuinely beats the alternative.

What it changes

Layouts get simpler and targets get larger. Typing disappears in favour of scanning or voice. Offline stops being an error state and becomes a normal one. And the definition of done shifts from the feature list to whether a full shift can be completed without anybody having to think about the system.

None of that is expensive to discover early and all of it is expensive to discover after the rollout, when a device estate exists and a crew has already decided the system is against them.

The rule we work to

No field system is specified without somebody from the build team having done the work, or at minimum stood next to it for a shift. Where a client cannot arrange that, we say so and price the additional risk, because a field deployment specified from a meeting room has a well-established failure rate.

That site visit is the first deliverable in a field deployment AI engineering engagement, and it is routinely the one that changes the plan the most.