I used to review consumer electronics as a side gig, and one year Shure was nice enough to send me one of every in-ear headset they made. This was around 2005 or so. The gear was excellent, fantastic sound quality, but they all broke. Even the $700 pair. The cable got pinched or something. Shure replaced them (even though at this point they were out of warranty), and the replacement pair broke a year later. Wires suck.
Marshall headphones have a 9mm jack on the headphones themselves to solve that problem.
Not sure about that part - especially for bigger (over-ear) headphones. My last 2 pairs of wired sets all died because the cable or connector inside the headphones got loose due to mechanical stress. Resoldering was not an option since it was not possible to open the case in a non destructive fashion.
At least that failure-mode does not exist in bluetooth headphones. And so far I had not an issue with my pair (but it's only a year old). But long term the battery might certainly become a potential issue.