I'm not definitively stating that you aren't good enough. It isn't fact. It's my opinion, and unfortunately for you, my opinion is one of those that counts in this regard. I'm not saying that you're bad, by any means - please don't take this that way. I just don't feel that you're good enough to be Jounin in this particular setting, especially when being a Jounin requires more of you here than it does in other places with less strict storyline interests.