Because stock lives in one system and the ledger in another, joined by a journal somebody posts at month end from a report. Between counts, the balance sheet carries a stock figure that is an estimate.
Shrinkage, returns and adjustments then arrive as one lump nobody can break down, which makes the gross margin for the month a guess.
Inventory, warehouses and stock adjustments post to the ledger as movements happen, so stock value is a consequence of transactions rather than a periodic correction. Batch and serial tracking sit on the same records where you use them.
Multi-branch means each store's takings, stock and margin are separate cost centres on one set of books rather than seven files.
It is not a point of sale. Takings arrive from whatever you sell on, through the API or as a daily summary.
And it will not stop shrinkage. It will show you which branch and which period it happened in, promptly enough to ask why.
Gross margin by product, by branch and by month is a query rather than a rebuild, because the cost of sale posted when the sale did.
GST reports read the same transactions, and bank reconciliation matches takings against deposits without a spreadsheet in the middle.
Yes, as movements happen, so stock value is not a month-end correction.
Yes — branches are cost centres on one set of books.
No. Takings come in from your POS through the API or as a daily summary.
Half an hour on your own numbers is usually enough to say whether Books is the right place to start.