Lifetime of a flexi…interesting. I dont’ know but I can guess and give a vague answer.
It depends how many times you play the record. The more you play, the deeper the groove gets. The greater the tracking force, the deeper the groove. Flexi disc are very, very thin (as mentioned already) so I can’t imagine a long life before significant distortion or some other unfortunate outcome. That is why alot of cassette dubbing was done years ago. To preserve very thin vinyl records when companies were getting cheap on material. That and cassettes were portable.
On a side note, Did anyone here win the daughter flexi yesterday? I wanted to win it but bidding got expensive in the last 20 seconds.