First, you see yourself as the kind of person who could afford a Tesla. That’s about it.
When you tell yourself you’re the kind of person who could afford a Tesla your subconscious mind takes over, finding ways to help you afford it. Ideas start floating into your mind. But if you start with, “I’m too young to afford a Tesla” or “My income doesn’t allow me to buy a Tesla,” then your subconscious mind won’t bother going to work for you.
There’s a tiny moment, right after you notice your desire to own a Tesla, in which you tell yourself you can’t. You’d never notice it if you weren’t looking for it.
Worse, everyone else is walking around with their own limiting beliefs, trying to project them onto you. If someone in your circle of friends thinks she can’t afford a Tesla you’re more likely to think you can’t either. It takes a decent amount of mental jiu-jitsu just to avoid their thought projection.
Of course, this is more applicable than to just cars.
[I’m currently reading The Magic of Thinking Big. 10/10 recommend.]