It's a cliche because there is so much truth in that expression that it is at least half-true. You could make the same case for bad luck.
I advise the youth to regard life as a conveyor belt of opportunities rolling past you. Experiences, jobs, relationships, books, learning, etc. They roll by, but almost never come back. If you grab enough of them, some will work out. On the other hand, the same bad selections that life offers keep returning, don't they?
Investigating luck: Unlucky people miss chance opportunities because they are too focused on looking for something else
I have been lucky in ways that I had nothing at all to do with (raised in an educated, middle-upper middle class church-going American family with no divorce), decent genes, a functional and honest personality (despite my share of flaws which nobody really knows about but one of which happens to be a lack of talent for anything requiring talent), etc. However, I give myself credit for making the most of those gifts in my pursuit of happiness and satisfaction. I suppose that I "could have made more of myself," but I didn't want to.