Luckily, I had spent last few months developing a software for a popular sports betting site. If you are into sports betting, chances are you use that software :)
This gave me an opportunity to work behind the counter and see how they operate. I noticed a few particular secrets that I am going to reveal here. (The kind of things they don't cover in non-disclosure).
1) Very few (not allowed to mention exact percent) of the people who bet win.
2) People who lose have no recognizable order or pattern in their betting. I concluded they are just betting on luck.
3) Newspaper hints or news like "Manchestor is in low spirit", have big influence on bets made. Not surprisingly, they are proved wrong more than often. People who bet on those news lose the most.
4) The kind of people who actually take money have very high winning rate. Most of them were winning atleast four out of five times.
5) The winners 'wise guys' always use a system. You can recognize their betting style and their system.
7) The winners never place bet on all the games. They make mostly winning entries. Like a clever hunter they know how to sit and wait for the prey.
8) Most winners use statistics based software or systems. This becomes clear once you see their betting patterns.
9) Beginners are the ones to lose money. Most people don't continue betting beyond six months. Those who do learn the art of betting and take big rewards.
My lesson from the above - If you are into betting (sports, not casino gambling), don't do that without a winning system.