I love this Bertrand Russell quote: "It has been said that man is a rational animal. All my life I have been searching for evidence which could support this."
All you have to do is take a good look at the G-20 convention and protests going on this week in Pittsburgh to see that often we have no rational idea of why we do the things we do. For example, how do destructive actions promote change to help people? "The atmosphere turned destructive along Forbes Avenue, where storefronts, including Pamela's Diner, were smashed in. Windows at the campus police station also were damaged. Businesses on South Craig Street also were vandalized, including Irish Design Center and Quiznos."
You don't have to go to vandalism to find irrational behavior. You can pretty much look anywhere you want. In the book All Customers Are Irrational (5), the author talks about how, if you really want to predict future behavior, you absolutely do not try to answer with rational explanations. As it turns out, the answer to predicting future behavior is quite rational - you look at past behavior.
Trying to find a rational answer for why you do things is much more difficult than you think. Rather than the subconscious being that part of the brain that kicks in here and there but usually handles the most basic stuff and our conscious part of the brain being, well, the brain of the operations, it is the other way around - only about 5% of the conscious portion of our brains being used to make decisions, and it is usually being notified after the decision has been made.What that means is that you don't really know why you often do things, instead you are generally justifying why you did that after the fact.
Newsflash: we humans are pretty complex creatures. We are far more emotional and communal, sometimes in strange ways, than we are rational. Understand this, and we may have something that can help our businesses, our jobs, and our relationships.