There are multiple examples online. Jacks which no longer do stereo but only one channel, or that require "fiddling" with the connection or rotating the plug, or the risks of leaving a plug inside a socket for a prolonged period of time, etc. And it is really problematic since it is the jack which wears out, which is usually hard to replace; soldered to expensive equipment.

not parent, but it's often plating related.

The part is made with a specific dimension when plated; the plating wears off -- this produces an undersized spring component and results in a sloppy/loose fit.

it happens more with headphones with a very heavy wire or jacks that get plugs swapped very often.

it can be fixed by carefully using a pick to deform the spring further out, so people tend to think that if that's the case then it must be the spring itself getting lazy.