i think if you someone expert in gambling then anyone do not need to easiest way to earn profit if you are expert and skillful in gambling and i think these thing is very important in gambling.
I should say that is completely wrong what you understood about gambling because in gambling very important thing is luck to make some money and if you're not lucky for the day then all your skills will be wasted. If what you said is correct then by now many gambling houses should have been closed. Gambling is just for fun and don't think it is easy to make a profit just with gambling skills.
But you cannot control your luck while you can improve your skills, luck is just an extra thing that would give you more chances to win when it strikes and it only strikes sometimes so it is still better to master your skills so in the long run you have a chance to make money although it is not easy.