What is fanaticism?
It is to be unrelenting, unyielding, never stopping for a moment and always bringing out your maximum effort and power towards some goal.
It is to be a zealot.
Before why you should be fanatic, let's discuss how.
Being a fanatic has many benefits, but it is risky. Your first goal is to learn to detach yourself from your emotional state. Once you do this you have to look at the situation as if it's a hypothetical, maybe even out of this universe. And imagine what you would do and why, think it over, see all the perspectives and the results. Eventually, pick the one you think is best. This is now your course of action in the real universe. Most of the times, at the start, you would do well to test your theory and pick, to be more certain it will be as you imagined in reality too. The more experience you have, the less testing you need and the more you can lean on your gut feelings.
Once you are ready with the test and you are certain enough in your course of action and reasoning/ideology, it is time to become a zealot about it. It is a risk because once you commit yourself, you have to go to the very edge and if your enemy is dangerous, you may not even rest at the edge and just take the final risk and go over the edge. If they are not so dangerous, you can afford a brief time of vulnerability to reassess your reasoning and see if you were right. During this time you are no longer a fanatic and this destroys your momentum and the powerful force, and intimidating face you created, which a dangerous foe can abuse.
During the duration of your fanatic activity, it is good, but not required, to have a way to stop yourself when you start being wrong. While in a fanatic state, it is not easy to do this. One way is to set your goal with limitations and if while being a zealot you start crossing these limits, you know it is time to stop and you stop without thinking if its right or wrong. Think about it after you stop, it must feel imperative that you stop(make it part of your fanatism) (thus make sure the limits you set are set well). You can also use the council of people you trust, go to them for advice each day during the calm hours. They can tell you if you are wrong, just make sure you develop a relationship where you trust them, they trust you and you can both be brutally honest to each other. Or they will fear your zeal.
Being a fanatic is not just about direct confrontation or confrontation at all. It is about confrontation, but also about how you think, your mindset, the specific battle, every aspect of your life. A subtle/slow and covert operation can be as fanatical as a full-scale attack can be.
Treat it as a tool, but not the primary directive. It gives power to your ideas but is not the idea itself.
Why should you be fanatical?
The world is filled with timid people. People are afraid to lose, they are afraid of change, they are afraid they can't adapt. So once they find a situation they are comfortable with, they become timid. They want to stay this way forever.
Boldness alone will very often be enough to defeat timidness. Being fanatical is always a bold move.
The saying fortune favors the bold is true. For one reason because very few are bold, so you end up in a situation where few people are, so there are more resources and opportunities for you than in other situations. It also puts you in a situation where you must act, which makes you learn and gives you experience.
When you are fanatical, it makes your opponents see that they can't negotiate with you, they can't reason with you and if they are timid, they will fear the coming and seemingly unavoidable confrontation. So they will succumb to your terms one way or another. And you can be as cruel and demanding as you want, to make their defeat final and forever. To make sure they never again stand up and challenge you ever again. They will submit because they are already in the loser mindset.
If it is someone who will fight you, then your fanatism will make you fight like your life depends on it and it may very well depend on it if you truly are fanatical and risking as you should be. If the enemy is not as fanatical, chances are they will lose, because they are not really ready to lose all, while you are.
The result is that you will be an intimidating force to be reckoned with. And if you fall, it will hurt and pain is a great teacher, so you are much less likely to do the same mistake twice. Be fanatical about not letting a loss get to you as well, take losses as a learning experience and do it again and again and again, until you win or die.
Never do half-assed operations and never strive for anything but the very best and top position.
I probably missed or forgot something.