For example, Percy Harvin was a 5-star recruit from VA and I believe ranked nationally in the Top 100 of every major recruiting ranking. At the time most fans knew VT had no shot of even getting a sniff from him because of the style of offense Coach Beamer ran. I don't believe the coaches made very much of an effort (if any) to try to recruit him. For some of the recruits that leave the state, how do you know that isn't going on behind the scenes?

Another possible explanation is that the VT coaches may not have a great track record of helping players at certain positions get to the NFL. Even though Coach Foster was a great DC, he didn't have a great track record with DL playing in the NFL. So I can understand why a 5-star VA DL recruit would decide to go play for another school who has a better track record.

A third possibility is that some VA recruits just want to play college football in another state. Some may do it because they get more stipend money for being an out-of-state recruit than an instate recruit. It may even be more money than what they could receive from VT. Others may prefer another school's location to Blacksburg, VA. FWIW Sergio Render selected VT because he fell in love with the area. I remember reading somewhere he enjoys hunting and fishing. Tough to do that at a school located in a metropolitan area unless you are hunting/fishing for the 2-legged kind.

A fourth possibility is a recruit selects a school because it gives him the best chance to earn early PT. Right now, VT has at least 10 RBs on or projected to be on its roster come Fall Practice. It is unlikely VT will have 10 RBs on its roster when Fall Practice starts because players will either transfer out or switch positions. If a recruit plays a position (i.e. QB) that limits the number of players that can be on the field at one time, then depth at a position could factor in a recruits decision. For example, if a teams depth chart at QB looks like this (including future recruits):

1 r-SR
1 SR
1 JR
1 r-SO
2 r-FR
2 FR
3 recruiting commitments for the next 2 classes

and a targeted QB recruit would join the team in the next 2 years, then he might opt to sign with another team because it could be more difficult to earn PT with this team.