The air conditioner compressor is responsible for both pressurizing the AC system and keeping the refrigerant flowing. It is subject to wear every time the AC is turned on. Just like any other component on a vehicle, it will eventually fail and need to be replaced.
Usually, when a compressor begins to fail it will produce a few warning signs like the AC no longer blowing as cold as it once did, loud noises when the AC is switched on or if you see the compressor clutch isn't moving.
Suits NA 1989-1993