Sure, some people use "luck" as an excuse to not improve themselves, but you're perhaps underestimating the impact of "luck".

Luck isn't even mostly about good things happening to you, it's about terrible things not happening to you.

Born into a family where you didn't endure 18 years of violence and yelling, causing your fight or flight response to severely interfere with your development and learning? That's pretty lucky.

The company you work for didn't shut down or lay off several thousand people nation wide, you being one of them? That's pretty lucky.

You didn't suffer unexpected medical complications leaving you bedridden or with poor mobility for months, interfering with your ability to perform your job? That's pretty lucky. Especially if you live somewhere like America where the medical bills can set you back several years wages.

Your house didn't burn down taking all your possessions with it, including your vehicle, just weeks after your previous vehicle was half melted by the car next to yours lighting on fire in the parking lot while you were at work? That's pretty lucky.

I could go on and on with situations I've seen friends and family go through that they had no real control, forewarning, or way to prevent. Luck isn't the primary thing that made successful people successful, that was willingness to take opportunities and hard work (with some exceptions). Luck is the thing that kept them from having giant negative life events to hold them back from success.