Commercial entrances fail in predictable ways. Here are the ones that come up most, and what is usually behind them.
It slams
Almost always the closer. A door closer has two adjustable speeds — the main sweep and the final latching action — and they drift out of adjustment or get knocked. A slamming door is a liability and an accessibility problem, not just a noise complaint, so it is worth fixing quickly.
It will not latch
Either the latch speed is set too slow to drive the door home, or the door has dropped and the latch no longer lines up with the strike. Both are adjustments. If neither takes, check whether the door is still square — a racked door will not consistently meet its strike no matter what you do to the hardware.
It drags on the floor
The door has dropped, usually through worn pivots or hinges. On a pivot door the bottom pivot carries the weight and wears first. Replacing worn pivots and resetting the door is routine. Grinding the bottom of the door to clear the floor is not a repair; it is a way of hiding the problem until the door is unsalvageable.
You can feel air around it
Weatherstripping and door sweeps are consumables. They compress, harden and tear, and on a high-traffic entrance they are an annual or biennial item. This is the cheapest thing on the list and the one most often left until somebody notices the heating bill.
The threshold is loose or a trip hazard
Thresholds take enormous abuse and their fixings work loose. A raised or rocking threshold is an accessibility failure and a genuine injury risk. Re-fixing is usually straightforward; a corroded or deformed threshold gets replaced.
The glass keeps getting broken
If the same entrance goes more than once, that is a specification conversation rather than a repair one. Laminated glass stays in the opening when struck, which turns a smash-and-grab into a failed one. It costs more once, and it stops the cycle.
The pattern behind most of them
Look at that list: most items are hardware, not glass and not the door. Entrance hardware is a maintenance item on a wear cycle, and treating it that way — rather than waiting for a failure — is what keeps an entrance out of the callout loop.