An entrance door on a busy commercial unit cycles more times in a year than most building components do in their entire life. Almost everything that goes wrong with one is a wear problem, and wear problems are usually repairable.
What is serviceable
Closers are rebuildable or replaceable, and most complaints about a door slamming or refusing to close the last few inches are adjustments rather than failures. Pivots and butt hinges wear and get replaced. Locks, panic devices and exit hardware are separate components. Thresholds and weatherstripping are consumables — they are meant to be replaced periodically.
A door that has become hard to pull, or that catches on the threshold, is very often none of those individually. It is a door that has dropped slightly out of adjustment, and setting it back square costs a service call rather than a replacement.
What is not
Aluminum entrance doors are built from extruded stiles and rails joined at the corners. Under years of heavy use those joints loosen and the door racks — it stops being a rectangle. You can see it as a diagonal gap when the door is closed. Once a door has racked, adjusting hardware only chases the problem around.
Impact damage to the stiles, corrosion at the bottom rail where water sits, and genuinely obsolete hardware are the other three. On that last one: if the closer is discontinued and nothing current fits the stile preparation, you can be forced into a new door by a component that costs a fraction of it.
Narrow, medium and wide stile
The stile is the vertical member at the edge of the door, and its width determines what hardware will physically fit. Narrow stile maximizes glass area and suits light traffic. Medium stile is the commercial default. Wide stile takes the heaviest hardware and the most abuse.
A great many recurring door problems trace back to a narrow stile door on an entrance that needed medium or wide. No amount of adjustment fixes a specification mismatch, and that is the case where replacement genuinely is the cheaper answer over five years.
How to decide
Ask whether the door is still square, whether the hardware you need is still available, and how many times this has been fixed before. A square door with obtainable parts should be repaired. A door on its third callout in eighteen months is telling you something about the original specification, and repairing it again is the expensive option.