Many of us have heard the following story. Whether it is truth or an urban legend is unimportant.
On the day of the final exam in a college philosophy course, the professor wrote a single word on the chalkboard: "Why?". The students began to scribble furiously, except for one who jotted a couple of words and promptly handed in his bluebook. He got the only A in the class, for the answer of "Why not?"
Both of these questions play an important role in life. One's quest for self-discovery can begin with either one. "I'm tired of working in a cubicle...why?" "I want different things than my parents did at my age...why?" Or, alternatively, "I've never traveled more than fifty miles from home...why not?" "Nobody in my family has ever graduated from college...why not?"
Which one is more important, though? Which of "why?" or "why not?" leads to more growth and change?
"Why?" is the question of investigation and uncovering. It leads one to explore the unknown. Whether what you find is a Good Thing or not is part of the whole journey. "Why?" was the question asked by Archimedes and Galileo and Louis Pasteur.
"Why not?" is the question of testing boundaries and debunking. It leads one to challenge the known. Again, there's no telling whether or not your experimentation is a Good Thing, until you do it, and sometimes not for a while afterward. "Why not?" was the question asked by Columbus and the Wright brothers and J. Robert Oppenheimer.
Which is more important to you? It depends on where your life is at the moment. Would you benefit more from setting off into uncharted territory, or by pushing against the barriers of your existence? Either way, your scope ends up being broadened. Sometimes it depends on which one is easier for you to carry out at a time when you desire change. Maybe it's too tough to break down a wall, but you can try opening a door you've never opened before.
Whatever the question, the most important thing is that the question is asked. If you feel you have all the answers, you've learned all you wish to learn in this life...and a life without learning is a life not worth living anymore.