I don’t encourage the use of “why?” it’s overly vague, and allows a myriad of subtle linguistic dodges. When you next use “why?”, try to determine which sense you intend the word in. Many “Why?” type questions derive their difficulty from the indeterminacy of the word “why?”, rather than the actual complexity of the question.

The question “Why did you do that?” can mean:
What caused you to do that?
What were you thinking when you did that?
What did you mean to accomplish by doing that?

If you find that you ask a question with why, but don’t know how you could substitute the “why” out for clearer language, you have not decided what question you are asking, and so you can not receive a correct answer.

“Why are we here?” is a popular question reducible to
What chain of events led us here?
What are we meant to be doing here?
For what purpose are we here?

Deciding which question you mean to ask is an important step towards finding an answer. “Why” is not the only word with such problems.