Outside of a few elite prospects, very few recruits get a quality evaluation from the experts. How does anyone truly know whether one player will be better at the next level? It's almost impossible in most cases.
There are so many things to take into account at the next level. How do they respond to challenges? Are they mentally tough enough to respond to adversity? Do they take coaching in a positive manner or take it personally? Can they compete against players as big, strong as fast as they are? Do they love the game enough to dedicate themselves to getting better? Do they have a true killer instinct? Are they willing to sacrifice individual attention for team success? Can they go to class and take care of business off the field?
None of that comes into play when looking at height, weight, 40-times and strength. Sometimes you just don't know whether a recruit will be the next stud or bust. It's definitely an inexact science.
Everyone wanted LB Daniel Brooks out of a Class 5A high school and ended up at Tennessee. He got kicked out for various issues and finished up at Jackson State. Meanwhile, LB Patrick Willis was a Class 1A kid that barely got an offer from Ole Miss and yet became an All-American and first-round pick.
If Tennessee had it to do all over again, there's no doubt they would take Brooks over Willis because he had all the numbers and just looked like a better prospect. Coaches will take a risk on a big-name prospect any day over a small-school recruit who isn't as big or fast.