A storefront door that will not close properly feels like it needs replacing, but in most cases the door itself is fine. Closers, pivots, hinges, locks, and weatherstripping are all replaceable parts, and swapping them restores the door for a fraction of the cost of a new one.
Repair is usually the right call when the frame is straight, the corners are tight, and the glass is intact. Even a door that drags badly is often just sitting on worn pivots.
Replacement makes sense when the door frame is bent or cracked at the corners, the door has been forced and twisted out of shape, or the building is upgrading to a different style or accessibility requirement.
The honest answer comes from an inspection. New clients get the estimate and the visit at no charge, so it costs nothing to find out which situation your entrance is in.