We use a whole 10%? Jesus! Most of the people I know use 1% at most.

Simply because the active parts of your brain converges and tries to block the bullet, this is just instinct.

The brain is made up of electronic circuits (not industrial grade, but ecological) and as the bullet is made of metal it acts as an inductor, thus creating an overload in your brain which forces you to shut down. Ergo you die.

Because it ricochet all over inside the skull, so it hits everything.

my brain works 100%

Because we use 10% of our brain power and not 10% of our brain, physically.
Yes, I'm fun at parties.

https://en.wikipedia.org/wiki/Ten_percent_of_the_brain_myth
I never go to parties :)

1. This whole 10% brain usage is myth.
2. If we are talking about small calibre - bullet itself can kill if it harm some vital parts, it can also kill because of change of blood distribution to vital parts/change of blood pressure inside brain. Actually 10% of people shoot in head with 9mm are able to survive (ofc with medical help).
3. If we are talking about big calibre - it's kinetic energy is so big that all fluids inside skull start to boil. Add to this fact that all that fluids and tissue is closed in small area (skull) and you will have similar effect to putting whole egg inside microwave. So if you shoot somebody with magnum his head can literally explode.

Not everyone dies from getting shot in the head! You'd be surprised the things people survive...
Though its definitely a rarity.

Please don't perpetuate these myths.
I know some people who act like they only use 10%, hell, we've probably all been there thanks to Erdinger Weizen ;)

have you ever thrown a rock in a small pond and only 90% of the surface gets distorted?

I use 110% of my brain power

Easy, just look at Homer's X-Ray and you'll see that the bullet will bounce back and forth until it finds that 10% since his skull is mostly empty.

View attached image.

Thank you very much!