Depending on the type of filter or motor you have, some of the problems can be worn out, ripped or damaged parts. This will cause your filter or motor to under preform and can lead to poor water circulations that will takes its toll on your overall pool quality.
Filter Grid Issues
Torn or worn out filters
Breaker keeps tripping and stopping your pool motor from running. Motor capacitors fail and keep your motor from turning on. Wire shorts cause motors to start and stop when exposed wires move around.
High pressure can take its toll on equipment over time. Small leaks rob the circulation and slow down the filtrations and pump capabilities. This can lead to poor equipment performance and cause water quality issues that sometimes you cannot see by looking at the pool. Your only clue is consistent dirty water.