In the famous talking-to he gave to a young Napoleon Hill before Hill went on the 20-year quest that birthed Think And Grow Rich, Andrew Carnegie explained that man's greatest breakthrough happens when he faces immense failure.

Failure, Carnegie explained, led to breakthroughs because a failed person would be forced to think, and think deeply, about what caused the situation. Otherwise, without a serious setback that leaves a man with nothing but time to ponder what went wrong, man neglects to explore the full depths of his mind. He never thinks fully nor accurately, thus never reaches his full potential.

So many examples of this being true when you listen to the backstories of people who have become highly successful. Tim Ferris. 50 Cent. Jay-Z. Tucker Max. Robert Greene.

So how can we create this without everything falling to pieces around us, or nearly losing our minds, or getting shot?
Force yourself.
Basically, place yourself in a state of mind that forces the same type of reflection that would happen if you had been fired from your dream job or you were 38 years old and not deemed successful by any measure. Reflect on things in your life -- the good, the not-so-good, and the blah -- as if they're the exact reason for your failure. This frame of mind forces you to hold nothing sacred (because it all led to failure in some way), question everything you know (or think you know), and open your mind to all possibilities (because what you were doing before certainly isn't the way to go).

Most people never come anywhere close to success not because they fail a lot -- that would force thought. Most people never approach success simply because they don't fail hard enough, don't have to reassess everything, are never forced to think. Things are not great, but not bad enough to induce this level of thought. Thus, the bliss of ignorance (of how great one could be).

Do this enough and some breakthroughs will happen, before or even without the breakdown.