His entire life was spent searching for limits, and then breaking them.
Not out of any sense of self-aggrandizement, nor a need to prove himself as being superior to anyone else, nor any of the many reasons most people sought out barriers to conquer.
The limits of what humanity knew, what it could achieve, they were holding humanity back, and he knew that if he could break through enough of them, humanity would be freed.
It led him to the stars, to the edge of reality, as he knew it. Then he broke through it.
And set the Masters free.