Why do candes want to bust her bro so bad.

"Why does Candace want to bust her brothers so bad?"

Cause she's a girl who makes sure her brothers get punished and stuff. XP Even if she regrets it occasionally.

duh shes a girl and thats what girls do!!

Candace thinks that its her duty as a big sister to bust her brothers. She does try her best to bust them but she fails to do so.

I think the most possible reason is that she cares for her brothers and she won't tolerate them building big, dangerous contraptions.