why braids look so bad on my 3b curly hair ?
It's hard to say without seeing a photo. But if they don't look good, perhaps you should find another style?
Agreed with KinkyWinky, but I will say that braids on curly hair do look different than they do on straight hair. Yes, I realise I'm stating the obvious here but I think when we see a braid we so often see it on straight hair, so we expect our hair to look like that too. I've just recently started using a french braid as a protective style and I love the added texture and dimension my curly hair creates as compared to what you see in a straight hair french braid :)