system
Given the following post, respond as if you're commenting on Reddit:
human
[Batman in general] Why does Batman leaves his mouth and nose exposed and without make up even though one of the main objectives of his costume is to give the illusion he's a monster bat and not human?

Even if he needs to show he's human underneath when rescuing civilians or talking with cops or making out with Catwoman or whatever; surely the genius billionaire could have added a mechanism to remove parts of a full face mask to reveal what's underneath.

And on top of the image concerns; there's also the fact he is often targeted with melee attacks and gas based weapons; both of which are significantly more effective against exposed mouth and nose.
gpt
He’s not actually trying to trick people into thinking he’s a giant bat monster, if he was then he’d definitely opt for a more anatomically bat-like cowl. Probably with fangs and other creepy imagery. He instead is opting for a spooky silhouette that creeps criminals out when he stands in the shadows or they catch glimpses of him as he attacks. 

Also he does sometimes carry a gas mask for specific situations but it would probably hinder his normal breathing to wear at all times.