If there are 100 people that have not gambled before but about to start. If they tell them to gamble and people are seeing them while gambling. Not all of them would first win. Some people will win while some people will lose. I know someone that gambled for the first time that lost the game immediately and he told me he is no more gambling again.
That's the reality in gambling, some may lucky and win, while others have no chances of winning but lose them all. This is also a proof that luck can happen any time, not actually in the beginning. However, just because we often hear successful gambling stories at the start of their gambling career, this become a reason for some gamblers to believe that beginner's luck exists.
Often hear this story in my local pool where they say beginners are usually luckier at the beginning, there are also those who say new accounts at new casinos are usually given high wins, but it's all a myth because the main factor in gambling is luck.
The problem I see when a newbie plays gambling for the first time is losing.
Then someone who keeps losing tries to create a new account as if they are a beginner - losing too.
So indeed the luck factor at the beginning for beginners does exist but it will not be much.