I get the premise, but can't we just use the already-established English words instead of misapplying a part of speech to make a cool book title or to rent a motivational speaker. Instead of finding my why, can't I find my purpose or my reason?
The quick search on the left reveals that the word in question is, first and foremost, an adverb. It is a word we use to question for what reason or purpose, but it is not the reason or purpose. Reason and purpose are nouns. They are the things we look for and develop; we cannot develop an adverb.
I know, we can look further down on the Google search page to find that why is also an exclamation that expresses surprise or indignation, but that doesn't address anything in this discussion.
You can find more rants on my Professional Pet Peeves page.