"Why" is one of the basic questions anyone can ask. One would say it’s one of the most fundamental and usually most difficult to answer. It is the epitome of curiosity, and also the foundation of science & progress in general. It is what makes Homo sapiens stand out. And it’s no accident that you’ll probably hear it a million times from your children as they grow up.

But I would postulate that in the mechanisms of the mind (and here I generalize; I don’t refer only to the human mind) why is not the most basic of the questions. In fact, I would say that it comes 3rd in terms of priority: after What and How.

"What" is the first question that our mind tries to resolve, always at an emotional level first. So, you see a pattern and you automatically ponder "What is this for me? Is it good? Is it bad?". In other words the first question that your mind needs to answer is what kind of pleasure or pain should I expect to receive from the pattern/thing in front of my eyes (or in my ears, etc). Of course you will use your previous experiences to derive the answer to this question (what did it feel like the last time we crossed paths with something similar?). But it doesn’t necessarily mean that you will get a detailed answer from your pondering. It will not bring to mind a series of past experiences like a movie passing through your mind with all the best and worst highlights of the past. No, it needs to be fast, in order to be effective. So you’ll get a gut feeling, a simple emotion (or a Driving Pocket as I like to call it in Noesis Theory terminology) that will combine the most relevant past experiences, to guide your next steps towards your pleasure hunt & pain avoidance.
This means that you might see a new person with a face that looks familiar, and you will automatically get a positive or negative predisposition towards him/her depending on what type of feelings you had connected with those persons of the past that looked like him/her. And you may not even stop to notice that your behavior was altered because of this. Or you might see a food that had caused you a heck of a stomach ache some time in the past. Immediately you will get a strong feeling of disgust, but this doesn’t mean that you mind will automatically explore the "Why" you are getting this feeling. It might even be unable to bring back the full memory, but the feeling has remained, in order to be able to swiftly answer the What.

"How" is the next question that your mind will tackle, and it’s usually action-oriented. Ideally the answer is a walk-through of how you need to act to deactivate your Driving Pocket that was activated by answering the What, i.e. how to avoid the pain or reap the pleasure. Usually you have a series of action sequences that you can activate on demand to cope with your most common action needs; you built all those during your lifetime, you don’t need to revisit them. They may need some finetuning along the way, but you can start acting and you’ll adjust as you go along (what I call Fuzzy routing in Noesis Theory terms). What is important to note here is that you can jump from the What to the How without ever questioning the Why. This is very meaningful for survival, but also thought-provoking (and a bit disappointing) if you generalize for what it means for the human nature.
It is meaningful because investigating the Why (i.e. thinking about it to bring the full past experience to mind) will certainly need time and there are many cases where time is of the essence and can translate at minimum to a lost pleasure opportunity (the deer I was hunting escaped) and at worst to the loss of your own life (I paused to think what this ominous sound from behind might mean and got eaten by the lion). Thus it really makes sense to connect the How directly to the What, in order to forward to action directly as your Driving Pockets get activated (with the prerequisite that you have a suitable action handy).
But this is also a bit disappointing for the human nature in general. Because it means that once you connect a feeling, a need, a pattern with an action, then you act without thinking of it too much or doubting Why you are actually doing it. This is very worrying because it translates to a huge manipulation potential for the human race. Actually, it may be happening already! If "the system" convinces you that this is the proper way of reacting to things to cover your needs, then you’re set for life. You might not even question them again, and act in the same way, day in and day out. Go to work, take the kids to school, pay the bills, watch tv, etc. You are welcome to replace "the system" with any other word of your choosing (the government, the religion, the capital, the Illuminati, your parents, your spouse, …) and built your conspiracy theories 🙂 But the fact remains that once you connect the What with the How, if you don’t receive external stimuli to break you out of this loop, you can continue looping ad infinitum without really questioning again the Why.

Finally, let’s look at the "Why". I didn’t want to mislead you that this question is not important. Indeed it is, and it’s the main way with which we build new knowledge. It is asked when we know the What but don’t know the How. Or similarly if a How we know more-or-less matches but it doesn’t perform the way we expected it to (i.e. bring us pleasure or stop the pain). Only then is the time to sit down and think, to explore better the memories of the past, investigate into our own experiences, try to combine different thoughts & concepts together to devise a new How. Therefore, Why is an important question, as it promotes learning and enhances survival, but it has to take the third place behind What & How which are prerequisites for survival.
That’s why I mentioned at the title that Why is overrated. We tout to value it above all else, but in our day-to-day lives, we rarely use it. Most of our activities are a programmed sequence of stimuli->reaction (What->How) and to pause and think about it is a notable exception. We live the lives we were taught to live, we provide pre-baked solutions to all the problems we were taught to handle, we limit ourselves to the boundaries we were taught that exist, and seldom do we pause to really ask ourselves. Why?