YouTube success: luck or skill?

I’m struggling to put my finger on what I should do to grow a YouTube channel. I’ve heard ‘just be original’, do this, do that. I have tried basically every approach, but I’d really like to distill what it is that pushes a channel over the edge. That way, I can put in the hard work without focusing on the wrong areas again.

Maybe I should post heaps of varying content, and just wait and see if something sticks?

I could be way off here, maybe someone with more experience can shine a light on something I am maybe not understanding.

Thanks