Late to the party on this .... But most capacitors these days are a lot like light bulbs. They will go bad in "X" number of run hours.most of the time less than X .
If you look up the old GE data on their capacitors, they are rated at 10,000 hours or more.( down here may that be 8 years or so)
The cheaper aftermarket ones may fail almost instantly from time to time.
I've never really understood why no supplier carries GE capacitors( besides oem replacements) . Ge caps last the longest .
About AMRAD capacitors........ That is the only brand I will carry now on the truck (because they don't break) and I try to get others to follow suit, however, understand that there is, or (was) a Chinese version of that brand. make sure to look for the american flag on the box!! AMRAD had many failed caps with the asian made units in southern US climates. The Johnstone location in New Orleans where I get them from "tries" not to carry the non us version .....but that don't always happen .