If I'm not wrong gambling means a guessing game and nothing is guaranteed.
That's right. Gambling on random numbers is purely about luck. There are plenty of snake oil salesmen pushing systems and scripts that make false promises that they increase your chances when that is actually impossible to do. They usually come with the proviso that you sign up to the snake oil salesman's referral link and they are actually designed purely to maximise the referral commision by trying to roll over the same coin as many times as possible.