Why do they refer to some guys as a tool?

Question

Ive heard it before and was curious. What is it?

Answer 1

if they're jerks, ignorant, annoying.......see where im goin with this? :P

Answer 2

When you call someone a tool, it's usually because they're a suck-up (brown-noser) or plays 100% by the book.

You call them a tool, "to the man" perhaps, because they can be used to make sure things go as planned by those in charge.  They may not even get any reward from doing so, which makes them extra toolish :-)

Answer 3

I'm not sure. Sorry!