Show me someone who says that for them luck is a factor, and I'll show you someone who's either defining their goals irrationally or dishonestly, or (more likely) someone who isn't giving 100% and is not actually choosing success.
Luck is a factor for those who claim to have a goal but only go at it half-hearted and half-assed. Luck is a factor for them, indeed, but that's because they are not really choosing success.
Imagine getting cheated on by your spouse, and then the spouse says, "Oh, I had a goal to not cheat on you, and I worked really hard at it, but, you know, bad luck struck."
Of course, they won't say that. When someone isn't taking full self-responsibility for all of their choices, they start defining their goals in irrational or dishonest ways to make it seem like they "tried" and failed. But there is no try. To try is to lie. Success is a choice, but those who don't choose it will often lie, including lying about what their real goal is, including lying themself with denial and self-delusion.
Even if you have a wild goal like becoming a millionaire, success is still a choice, 99.99%+ of the time.
It's as infinitely easy (just a matter of choice) as it is for a spouse to not cheat or an alcoholic to stop drinking.
Of all these things, failure-choosers will say it's luck not just choice. They are wrong, and almost certainly lying to themselves too.
Success is a choice, but most don't choose it.
And those who don't choose success struggle to fully accept the truth of the phrase "success is a choice". It can be met with anger, denial, or other cognitive dissonance.
Addicts find comfort in pretending to be out of control and in blaming imaginary phantoms for their torture rather than admit they are really their own torturer, and rather than admit they are in 100% full control of their own happiness.
All humans are on the addiction spectrum.
What about you? Are you pretending to be out of control, pretending to have goals that are not really goals but just try-ridden wishes about so-called luck? Or are you honestly looking at all the infinite things you can do and all the things you can have, and then, from that huge wonderful menu, choosing what you want with infinite ease?
As long as you are honest with yourself and others, you will look at the right menu. As long as you look at the right menu, you will know that success is a choice.
Choose it and you'll be successful. Don't and you won't.
What you want you can have. But you do have to really want it, and you do have to really choose it.
"The mind is a wonderful servant but a terrible master."
I believe spiritual freedom (a.k.a. self-discipline) manifests as bravery, confidence, grace, honesty, love, and inner peace.