I am just completely unable to wear white shirts without ruining them

Of course if they are poor quality, old, or already stained, then that is fine, I will literally never get a mark on them, and if I do, it will wash off easily.

If I buy a brand new shirt though, I will undoubtedly ruin it the very same day, even if I haven't yet worn it. This happens every single time.

Yesterday I pulled a basically brand new shirt out of my cupboard, saw it was marked, and set it aside to clean later. I don't remember getting it dirty, but it looked like sand / rust / dirt from my recent trip to B&Q. I sprayed it with oxygen bleach, which did absolutely nothing as usual, despite assurances from TikTok that oxygen bleach is the best, and super powerful, so instead I scrubbed it with soap, but it was stubborn and I didn't make any progress at all.

Half a bottle of white vinegar and several tablespoons of baking soda later, I was able to get the stain out by scraping the fabric roughly with my fingernails. Great. Then I put it in the washing machine to wash off. I took it out just now, and it has another gigantic stain on it, on the back somehow? Who is doing this to me? Myself? I hate that guy!