I guess you answered your own question. Because Beechwood is a very good team, regardless of class. And Prestonsburg appears to be very inconsistent this year. Note their last 2 games where it looked like they didn't even show up.
It looks like P burg has the capabilities, but doesn't always play with it's heart. I'm not up on Prestonsburg this year except for the scores, but their inconsistency is obvious. Either they are not playing well of late or the other teams are preparing for them better.