Boogers...what's that for?

The air we breathe contains a whole host of dust, germs, and pollen, and if these particles went straight into the lungs, our breathing system would be damaged.

Mucus or snot, the preliminary form of a booger, prevents this by tapping the particles and keeping them in the nose.
After some time, the snot surrounds them along with some cilia "the tiny hairs insided the nose", and dries them down.
And so welcome: the booger.

Boogers, in fact, indicate that the nose is working properly.
But don't let it stay inside your nose.
Hahaha