Because the factors change...
A lot of people can win if they inherit a program from a championship level coach.
Bobby Cremins never won or played for a championship.
Matt Doherty says hi from UNC. So do all the failures at UCLA since Wooden that stalled. Steve Lappas was awesome after Rollie. Billy G followed Tubby. Padgett followed Pitino and missed tourney with Pitino players.
I could go do research and find countless examples that show guys taking over "championship level" programs failing.
Others run with it successfully. Roy. Call. Self.
Some have 1 random run. Like Davis Ollie and Hewitt. Your guy Shaka. What championship coach did Shaka follow at VCU?
Larranga George Mason.
It happens.