Why don't soldiers wear a bullet proof suit that covers head?

Why don't soldiers wear a totally bullet proof suit which would cover from head to feet?

Because survival is about more than just being able to resist hits.

This is the Onion Model:

Don’t be…

Detected

Seen

Hit

Penetrated

Killed

What your armour tries to do (in the diagram: Don't be...penetrated) is actually pretty low down the list of preferred options. Crucially, past a certain point stacking more body armour onto the PBIs makes them less mobile and less stealthy, which makes them more likely to be detected, seen and hit.

So there is a point at which adding more armour actually becomes counter-productive. The guys are probably wearing about as much as they can realistically be expected to carry as it is.


Source: QUORA

I did not think so. It was interesting to learn.