I meant President/VP/admin are responsible for monitoring mods, I didn't mean global mods to clarify. As freemind put it the only reason global mods are in the position they are in is because they no longer require supervision.
Yeah now I understand. Thanks again for the clarification. It's a big responsibility, though I mean no supervision that's like he is free haha. In the real world, giving such power to a political leader will do bad things to the economy not saying he is bad, just to clarify just sharing my thoughts. 
Not
requiring supervision does not mean global mods aren't supervised though, that's maybe another point I didn't explain well here

Global mods are also able to all keep an eye on each other through mod logs, even if president/admin hold that
responsibility to make sure there aren't issues. We all make mistakes and all it takes is a pm from another global mod to resolve simple issues, without needing interference from anyone with "more" power. We've otherwise never voted in a bad global mod, simply because it's always been based on their moderating ability being at a high enough standard already.
We also often work together to resolve issues, there's a lot behind the scenes that users don't see basically. It might give the impression that global mods all work independently from each other and without any supervision or oversight, but that's far from how it really works, even if GMs often work in their own ways and in different areas of the forum.