I have the believe that success in gambling requires a mixture of luck and skill. This is opposed to some people that believe that gambling is entirely a game of luck and others who believe it is entirely a game of skill.
There is no gambling games which is 100% based on skills, even in sports betting and pvp poker, luck is still taking a big part in the outcome. I wonder who are those people who believe that there is a gambling game which is entirely game of skill? You can be very talented and skillful sports bettor or poker players, but when you are out of luck, your skills and knowledge cant give you a win.