The number nobody trusts
Reporting
A hospitality operator, reviewing the till system they run their business on, wrote that the data in the reports is sometimes inconsistent, and gave cost of goods as the example. Not missing. Inconsistent. The report runs, produces a number, and the number is wrong in a way nobody can predict.
Look underneath and the cause is usually structural rather than a bug. The same system cannot model a composite item and a variant at the same time, so a meal deal with a choice of drink has to be entered as something it is not. Another operator described exactly that: a value meal with a free drink attached, and no honest way to record what actually left the building.
Once the entry is a compromise, every figure downstream inherits it. Stock decrements against the wrong item. Cost of goods drifts. The report is not lying so much as faithfully reporting a fiction that was agreed at setup and never revisited.
So the manager recalculates by hand before anyone senior sees it. That hour is real work, it appears on nobody's rota, and it continues for as long as the item structure cannot express what the kitchen actually sells.