Headphones

So, i've had 3 pairs of the dt990 pro, and on every pair, the sliders have broken on both sides. first the left goes, and then the right goes.

now im not heavy handed, nor do i abuse them, but i do wear them daily. i knwo they sell a repair kit, but its the same plastic that breaks, and they havent revised that to make the piece from a better or stronger material.

it isnt like the headphones are super expensive, but theyre also not cheap.... so why are they so anti consumer, and why do they refuse to help even while you're in the warranty period?