Do you know that they maybe right, because if you study your games very well you be able to know the kind of game's you book during your prediction, but the thing is that some people doesn't have that time to study games very well, because I know that what makes some people to make a negative prediction that leads to lose in the gambling, is as result of wrong prediction, so they have to watch and understand games before we can book for wining, some people predict base on assumption.
If you are good at analyzing matches, you may be unlucky once or several times, but most of your predictions will be winning. But if you make every bet relying only on guessing, then the percentage of losses can be much higher, because even good analysis does not guarantee a win, sometimes unexpected results happen, but if you are a good analyst, then most of your bets will be winning. If it is just a bet on guessing, then the percentage can be very low. It all depends on your luck, but there are not so many lucky people.