In gamble, the most needed skill that you need to have is a lot of luck.
Luck is not a skill or part of your skills,. you must have misunderstand the meaning of it.
Let's say I am a gambler and I want to win most of the time,.. can I dictate my luck to be with me every time I gamble when I am not in control of my luck? Of course that is not possible, the best way is to improve your skills and choose a skilled based type of gambling.
If luck depended on effort/training, then professional athletes would win in the casino as in ordinary sports. In this scenario, gambling would be very boring - it seems to me that here the players are looking for and love some kind of miracle when any player can be better (more successful) than any other.