Frustrations

I've been a UI designer now for almost 2.5 years. Recently, I was given a project that seemed like a no-brainer. It was a static page with information which contained "global" information and "local" information. Easy right? Well, for some reason I just couldn't get it right. After multiple iterations, it still didn't look right. I went to my mentor for some feedback, which he also agreed it didn't look right. But after a few minutes of looking at it, he noted that it was a page for "settings".

Today, I showed the design I was working on to another senior designer, to which he noted, "this page has multiple personality disorder. It's for settings, but wants to be more".

So, why didn't I notice that it was a page for settings? Is this about lack of experience? After being in this field for 10 years, will I be able to look at a design and know exactly what its supposed to be?

It was really frustrating. I don't know if I should already know this stuff or what. While, I did learn something about this whole experience, I know next time I work on a page like this, what the expectations are. But, its times like this that I feel like I still have so much more to learn.
But, I guess that's the point.