Pardon me if this has been discussed before.

http://www.sciencedaily.com/releases/2011/05/110524070310.htm

Summary: When women look at a picture of a happy man, they find him unattractive. The same man projecting pride or shame is more attractive.

This is an inconvenient fact. Happiness is obviously the end goal for most men. Happiness also leads to more success and longer life. It is hard to conceal.