"protecting your own backyard" is that (theoretically) you have an advantage there, and you have a better chance of landing higher-rated recruits that otherwise might not be as interested in your program if they were in somebody else's backyard.

And to a large extent, BYU has done that, by landing the (infamous) "Lone Peak 3" and Brandon Davies and the Collinsworth boys from Provo High. And that has allowed for some success - just not as much as we hoped for.