Why are you vegan?

I'm not a vegan and don't plant on becoming one, but I'd love to hear why you are all vegan. A philosophy like vegetarianism is understandable because to eat an animal directly harms it, but I've always wondered why people decide to be vegan. I've heard that it's because animals are being exploited, which I definitely agree with in cases like chickens and bees, but why is wool considered cruel? I'll be clear I'm not trying to debate or attack veganism, I'm just very curious about it and I want to make sure I have a deeper understanding of the philosophy. Thanks!