Gambling is actually meant to increase what you have staked with, like you aim to increase the worth of money you have. If gambling is about to increase your money, do we gamble gradually or we have to take the risk by increasing our stake since it is the purpose that we are gambling, which is to make profit.
It's understandable to have this goal of gaining money through gambling. But did you ever think how possible it is to earn and just ignoring the risk? Many gamblers tried but only few are able to increase their money. Thus, it's better to gamble base on your own preference on which you think can benefited you most. Because regardless of your style (either playing gradually or increasing each bet) you're the one who can say on what you think is the best way to gamble based on your experience.