The more work you put into your channel, the more "lucky" you'll be.
In my world, luck doesn't exist. It's an excuse for people who are lazy and people who quit before they get success because they prioritize to play CS:GO and be with their partners. People like that believe in luck and they will also say that YouTube hates them and it's unfair they don't get views and subs, etc.
Sorry for the rant.
I’d say persistence and hard work really helps. I’ve had months I was so busy (had my channel 5 years) and I saw little growth on my channel. Lately I’ve been posting videos daily, promoting constantly and my views went up by about 20k in a months time. I make almost double and and I went from averaging 4-5 subscribers a day to about 8.