On the subject of personalities, I try to keep mine rather open and non-judgmental when I can, but I will admit that there are times when I slip up (especially if a strong moral value is at the heart of the problem, such as someone being abused).
Though, that's just how I see myself; truth be told, the very concept of a "douchebag" is mostly dependent on how other people see someone. I mean, there are some cases where the bitch/bastard's just rotten to the core, but most of the time, it can be described as "one man's villain is another man's hero." This concept is found commonly in a case of a two-party dispute, be it a political debate, a military conflict, or simply an out-of-touch couple arguing. Each person believes he/she is right, and likely have others who would agree with them on that. Hell, even the most infamous douches of human history (Hitler, Stalin, you know the types) believed what they were doing was right, and had followers who supported that notion.
My point is, the person you may see as a "douchebag" or a "prick" likely has people who think otherwise of him/her. After all, if people could actually agree 100% on how they saw people, we wouldn't have Bieber albums and Twilight films still making money, now would we?