NGC disappoints me

I purchased a 50 cent piece (2008S Kennedy Clad PF70). Upon inspection it had a very obvious flaw on the obverse. I would expect a little more from one of the top grading companies. It is not a minute spot that is only visible with a 10x magnifier, but it is in plain sight! I wear glasses, but I can see this flaw without my glasses. I was under the impresion that there were at least 2 or 3 people that reviewed each coin. There is no way this could have slipped by 4 eyes let alone 6!

What is up with this? Has anyone else had any issues like this?