What’s wrong with crouching?

I just started the game like 2 months ago and I don’t really know much about it but recently I noticed that whenever I kill someone crouching they would always get so angry at me in the chat saying “why are you crouching???” Or like “noob crouch” is crouching bad? Am I doing something wrong? if yes then why? Cuz i’ve never heard it coming from my teammates it’s always the opposite team so is it bad or good or what?

Edit: i dont crouch all the time the only time I crouch is when the enemy is literally in front of my face if they were far I don’t, bc if I did I’ll miss my headshots and its annoying, so my crouching isn’t like always