To become what you want to be, it takes a lot of pain. Most people when they hit this pain back away, or only stick with it for a little while before it becomes too much. It is only the greats who have been able to stick with the pain for a long enough period to see the results of their efforts.
So how come only a small percent of people are able to keep going through the pain, while others are not? Is it because they were created a step above the rest, or are in some way superior? Absolutely not. They simply have become comfortable with being uncomfortable. If you've been alive long enough, you know this world is full of pain and suffering. That's a fact you have to accept. To get anywhere in life, whether it's a new body, a new job, getting your business off the ground, etc, you know that it's going to take a lot of work, setbacks, and pain.
The pain doesn't hurt successful people any less, they simply have a different mindset. They accept pain as part of the process, and when it comes, they embrace it because their love for the process is greater than the pain they're feeling.
There's a noticeable difference between pain and suffering. Everyone experiences pain, but you don't have to experience suffering. Suffering is dwelling in the pain, and making it worse than it really is. Successful people feel pain, but they don't let it defer them from the success process.
You can be successful in any area of life if you start shifting your mindset to embracing pain, and becoming comfortable with being uncomfortable.