Do speakers wear out?

Electrostatics are probably wearing out from day one.
Dave,ex Martin Logan owner.:(

The speakers in my 1957 Ampex console have rubber surrounds and still sound great - no problems whatsoever. Even the crossovers are original. I also have a pair of Dynaco A25s from the 70's, also with rubber surrounds and they also play with no problem. Both speakers have that grayish dusty look to the surrounds, but the rubber is still very pliable.

Some old caps seem to last for decades with no stress, but in the UK, the components available to audio manufacturers were often of "radio/TV" grade and not very long lasting at all.

Where speakers were concerned, I don't think capacitor quality really came into it, as the designers had enough trouble with crossover design, the basic quality of the drive units and of course the boxes to put everything in - capacitor quality paled to (almost) insignificance, certainly with budget quality speakers IMO.

Things weren't always bad though, as the BBC derived designs used better quality parts all through and the caps used were of higher quality to start with and were individually measured and selected in the case of the Spendor and LS3/5A models (the early Rogers models may well have been as well).