Why do poker players seem to think they are great?

[black_russian]

I have been playing poker for a few years and the one thing I find in most serious players is that they think they know all about poker. Casual players or those purely playing for fun not so much. It just seems anyone who has read a poker book or discussed strategy with a friend thinks they have it figured out. One of the most common traits of these types is complaining when they lose to a flush but when they have the same draw they play it the same way and will then justify it to the guy he just beat who is now complaining. I am not complaining because I think this is what makes the games profitable but I am curious to others thoughts on the topic. What is psychogically that makes people feel they are superior to their competition in poker.