What is said by BetFury was correct and every single aspect should be taken in consideration while gambling.
First, many people just jump in the first game they see or feel they know it without reading the rules in most cases. Just how to play it especially if there was a similar version to it in another place. By analysing, we can include also the way we play, our tendance and expected movement that make us losing.
Second, emotions are an important part of the failure of most people. You won the first move, you want to increase your earnings fast, you lose then you want to get your money back as fast as possible. Without recognising it, these emotions make you take the wrong decision and make your next moves quite expected and silly.
Third point, simple goals = less risk and money to lose.