Every shop owner has had the same afternoon. The screen says fourteen. The shelf has nine. Nobody stole anything, nobody is lying, and the software is working exactly as it was told to. The gap opened up over months, one small habit at a time.

Here are the six that cause most of it.

Goods arrive before the purchase entry does

A delivery comes in during the rush. The cartons go straight onto the shelf because the counter is busy, and the purchase entry gets made that evening, or the next morning, or on Sunday. In between, every sale of that item is billed against stock the system does not think you have. The count goes negative, somebody corrects it by hand, and the correction is now the number everyone trusts.

The fix is not discipline. It is making the entry take thirty seconds instead of ten minutes, so it happens at the door rather than at the end of the week.

The same barcode arrives at a different MRP

A supplier changes the printed price between two batches. The barcode does not change. Now one number on your screen is standing for two different things, and the margin report quietly averages them. At the end of the year you cannot say which batch you actually sold.

This is why batch-wise tracking exists, and why it matters far more in grocery than anyone expects until they look.

Damages and expiry are never written off

A bag splits. A packet goes past its date. It goes in the bin behind the counter and never touches the system, because writing it off feels like admitting a loss. The stock figure carries that item forever, and the shrinkage shows up a year later as an unexplained gap nobody can account for.

Written off properly, it is a number you can manage. Left out, it becomes a mystery.

Loose items are sold by weight and counted by piece

Rice, dal, dry fruit, anything that comes in a sack and leaves in a packet. The purchase is in kilos, the sale is in whatever the customer asked for, and the packing is somewhere in between. Unless the system knows the loose stock and the packed stock are the same stock, the two counts drift apart from the first day.

Staff bill from memory when the queue is long

A regular customer, a known price, a busy evening. The item gets billed as something similar rather than scanned, because scanning means walking around the counter. The bill total is right, the customer is happy, and two different items are now wrong.

A counter that is genuinely fast is the only real answer to this one. If billing correctly is slower than billing approximately, people will bill approximately.

Returns and exchanges go back on the shelf, not into the system

The piece comes back, the customer gets another one, the first piece goes back on the rack. If that is not recorded against the original bill, you have added one to the shelf and nothing to the screen.

What the gap actually costs

None of these is dramatic. Together they are the reason a shop orders stock it already has, runs out of stock it thinks it has, and cannot trust its own margin report at the end of the year. The count does not need to be perfect. It needs to be close enough that you act on it instead of walking to the shelf to check.

If you want to see what your own counts look like when every one of these is handled properly, that is what a demo is for.