How long do high quality speakers "last"


I am the original owner of a pair of ProAc Response 2 speakers. They are almost 7 years old, but have never been driven excessively hard. How long (i.e. useful lifespan in years) can I expect these speakers to "last" (i.e. no significant sonic degradation) if I care for them carefully? When they do start to degrade, what mechanical failures and sonic degradations can I expect to occur? Thanks in advance!!!
mshan
The foam surrounds and electrolytics in the crossover are what will go first.

10 ish years on the first, 25 on the latter.  Keep them out of direct sunlight and excess moisture.
Won’t the wiring and other metal parts oxidize over time? Before I got Anticables, I was using Monster Cable. Every year I would cut off the ends and peal back the jacket to expose fresh (less oxidized) copper. It always provided a big jump in clarity.

My Wharfedale Opus 1 speakers are internally wired with Monster Cable. But there is no way for me to perform the same type of operation. And after 16 years, I wouldn’t be surprised if even the unexposed wire has some degree of oxidation since the jacket cannot perfectly seal around stranded wire. I have heard of people rewiring their speakers, which would solve the problem if there is one.