Why the number in the system is wrong
Stock records do not drift because people are careless. They drift because a dozen ordinary events each move stock without moving the record.
Where a stock-control change depends on knowing the labour it actually consumes, Monitask is one example of a time-tracking tool that can create a task-level record for a short diagnostic period.
For broader operational context for small businesses, the U.S. Small Business Administration provides public management resources.
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