Well, they didn't come up with nothing. They came up with patterns of incompetence and knowledge that we (as in Clinton and Obama as well as our intelligence community) knew it was a terrorist attack instead of some protest over a movie the night it happened (before the movie claim). This was illustrated by Hillary's email to Chelsea stating an al qeada stile attack and comments from witnesses and department heads. We know that the decision not to send a rescue team was a political one based on appearances instead of any logistical problems.
That may not mean much to you but it says we acted callously with regard to the safety of our diplomats because of political reasons which shows extreme incompetence to me.
The fact that you keep bringing it up and saying we found nothing is sort of telling. It somewhat says you think the same but feel the need to gloss over it. And the reason there was 9 investigations instead of just one is because the administration (not necessarily Hillary) kept stonewalling and facts were being discovered after the process was winding down including facts revealed by the eventual release of Hillary's email. Or in other words, the administration want it stretched out through multiple sessions of congress for whatever reason. Given what we know, it was likely a shrewd political calculation too.