Luck is made up of factors outside of your control. We're playing a complex multiplayer game with billions of players and trillions of moving parts.
For these notes, I'll define "skill","work", and "choices" as other sides of the luck coin. In all of these, maybe a better antonym of "luck" is "control."
luck vs. skill looks differently depending on the scale at which you view it. On a global sense, luck matters more. At a more localized level, skill matters more. Note that I'm using skill as a stand-in here for hard work, choices, etc.
Luck does not mean that things are purely out of your hands, and systems with variance can still some what be controlled.
As the saying goes, you can't make lightning strike, but you can wait for a storm, climb a tree, and hold a metal rod. (citation needed)
"I Don't Believe In Luck" - A worldview some hold, that success is dependent solely on how hard or smart they work. A refrain typically held by insecure privileged people to help them feel that they deserve what they have.
Luck and Success
"you're going to participate in what I call the Ovarian Lottery. And that is the most important thing that's ever going to happen to you in your life. It's going to determine way more than what school you go to, how hard you work, all kinds of things." - Warren Buffet
"Mild success can be explainable by skills and labor. Wild success is attributable to variance." - Nassim Taleb,Fooled by Randomness
When it comes to success, Luck matters more in an absolute sense and hard work matters more in a relative sense.
When looking at other's successes and failures, it's impossible to tell what is luck, what is skill, and what the ratio of the two is.
Absolute Success is Luck, Relative success is skill - James Clear