Well, the 質問 is kinda complicated, but I do my best to answer it.
Severus Snape keeps on making wrong decisions: - he has an ambition to work for Voldemort - a serial killer and psychopath - when he grows up. - he hangs out with the wrong people. - he insults his best friend, who always stood によって his side. - he ends up helping Voldemort and killing heaps of people.
Do あなた want your children to do anything like that? That's why he's considered a bad rolemodel.
He was never a good role model until the end. He bullied his students, he held a grudge against Harry, simply for bring his father's son and he only helped Harry because he liked his mom.
+He is mean to his students +He is a Death Eater +Hurts his students +Tries to get the most innocent kids expelled +Best フレンズ with Voldemort +Is the Half Blood Prince But he can be a VERY good guy!
