I was wondering if there are any studies done on this. I googled but nothing. I searched here too but nothing specific came up, so I'm guessing this topic has not been discussed in its own separate thread. But by all means, correct me if I'm wrong.
Maybe there is no data on this at all?
'Failure rate', as such, might mean different things to different makers - meaning, different price points - and thus some may not care since they're charging so much to begin with, and offer life-time service that also charges a lot.
And, the parameters determining 'failure' may be different for different makers. For example, some makers may consider inaccuracy by +15 sec/day to be dismal failure, while another may not recognize it as failure till the watch stops running altogether.
Take your standard, off the shelf ETAs, for example.
Wouldn't ETA want/need to have this kind of info? Or, do they not? If not, I would imagine that's bcz they don't accept returns once they've sold them to various watch companies. It would up to the watch companies themselves to figure out their own warranty, etc.