This is one of those things where hindsight is 20/20. Yes, in retrospect some system whereby you have every valve labeled and numbered like you would in a power plant, where you have a written maintenance schedule where you do things like exercise valves, and where you consider the lifespan of a component and replace them periodically makes sense.
But even if you do all that, you can still miss something. It's easy to armchair quarterback and say "oh, well of course if you run ozone you should replace seals every two years, and valves every five!" But none of this stuff comes with an operators manual as a whole.