I do this not for money or fame. Nor even responsibility. I do it for Insecurity. I have to protect my family, my friends, and my fellow citizens.
Everyone has a family, even the bad guys. Especially the bad, well-armed guys.
I never thought such a prosperous place as Gotham city could be such a depravation. But now I have to believe it, and, change it.
Partners with the same ideal are crucial. they may have weak bodies, but must have strong wills.
Batman is not a superman with super powers. He is just a human being.