The question asked most often in a workshop is plain: where is this piece now. Has it been cut, is it at edging, is it waiting for tempering, is it packed. The answer is usually as accurate as somebody's memory, and the date given to the customer rests on that memory. The job of a glass production system is not to remove the question but to move its answer into a record.
The way to do that is to give every piece an identity of its own. During cutting the piece gets a label; the label says which order, which position and which size it belongs to. As it passes a station it is scanned and the current stage enters the record. Scanning takes a couple of seconds and nobody fills in a separate form. The record forms as a by product of the work itself, which is why it survives.
Tracking systems designed as extra work are abandoned in the first busy week. An arrangement where someone fills a list in the evening or updates a spreadsheet at the end of the day lives about three days. That is where the difference comes from: a record lasts when it falls out of the movement that was happening anyway.
Network coverage in a workshop is not always the same quality. When a terminal loses its connection the scans are queued and processed in order once it returns. The operator does not think about the connection and keeps scanning. Otherwise the habit breaks at the first outage and never comes back, because an incomplete record takes away trust in the whole record.
With multi layer glass the flow is a little longer. What is meant by production tracking for insulated or double glazed units is that the order is split into its component panes and each one is followed separately. The same logic holds for laminated glass: what is tracked is not the order line but the piece passing the bench.
After a while the accumulated record starts answering its own questions. Which process waits the longest, which station piles up on which day, why a particular order ran late. These can be discussed from memory too; but discussed from memory everyone has a different answer and the discussion goes nowhere. A record produces a single answer.
Breakage is part of the same flow. When a piece is broken or cut wrong the fact enters the record and a remake is opened for it. The missing piece becomes visible the moment it happens rather than on dispatch day. The difference between the two is the difference between warning the customer a day earlier and apologising at dispatch.