Then why there are people who are consistently good with poker?
The more time a person spend in doing something the more the chances of getting accustom to the way the is done or function. Game of card is a game of chance which the chances of becoming more lucky to win from random is high combined with skill. Maybe I could say the higher the time spent in learning/doing something, the better the chances of getting it right.
However, it's only doable on games that are based on luck, therefore, it's important to focus on games that are proven could make someone win consistent money, and of course, as mentioned, card game, particularly poker is one of those.