Good question: why people resist arrest? Why not just obey the officers?
I used to think like you. I assume cops are the good guys and as law-abiding citizens, the best course of action is to just ALWAYS follow all their instructions. I used to trust them 100%.
Now I've learned how *SOME* police abused their power. *SOME* of them are just a-holes. I don't know how many, but a non-trivial number. So there is a distrust on both sides. The person being arrested don't believe he would be treated fairly by the police, and the police don't trust the person would be non-violent.
I still think the best course of action is to follow police instructions. But I've grown to understand why resisting arrest is a legit consideration for some, and not because they have criminal history.