Luck does not knock at the door because it comes to us. It is just like the magnetic field that revolve around the Earth keeping objects trying to accelerate above the scape velocity back to gravity. This is a force that can be attracted and also repelled when we misuse it. The Chinese and the Japanese know about it and I've learnt how to use it in their favour.
That's why Chinese and Japanese people believe in luck. Luck cannot be created or trained with certain methods. But luck can be attracted with positive energy. Chinese and Japanese people believe that good and positive things will attract luck from destiny.
Back to the topic, I think luck will still be needed in any game. In skill-based games you need your skills but no skill can guarantee your victory. In slot games you purely need luck. And in sports betting you can use your analysis to predict the outcome of the match but luck is also needed in determining your final result. Sometimes the team that you think will win 100% but loses surprisingly because there are factors of luck and unlucky from a team.