Why'd She Do That?

Did you ever read about a character making a decision or taking an action and wondered "Why did she do that?"  For example, why does the girl in the skimpy dress unlock and crack open her door after she's seen the TV news and knows there are zombies loose?  If you have to ask why, the author hasn't made the character's motivations clear enough.  Today I thought I'd give you one technique for avoiding that problem.

Engineers have a method called Root Cause Analysis (RCA) they use when...