Frost was the perfect fit for UCF at the time. Despite the winless season in 2015, which was a combination of the shittiest OC in history (Brent Key), major injury issues, kids quitting on tyrant O'Leary, and a very inexperienced coaching staff all-around (everyone knew GOL was close to retiring), there was a good amount of talent that Frost inherited for his first season. Several NFL guys as well as a highly disciplined defense (the one thing O'Leary always did well) with upperclassmen leadership.
So Frost came in and fixed some key issues that had been plaguing UCF for years:
1. The culture - GOL was an old school, Junction Boys type coach. He wasn't fun to play for, even though a lot of former players now say they appreciate how hard ass he was. Frost loosened up the culture and introduced fun all around the program. He gave the program an identity (UCFast) and did a lot of things that made players happier -- GOL didn't even allow music at practice.
2. He updated the offense from a pro-style to an adaptation of the Oregon spread. Less read option but still a lot of stretching the field horizontally. So he got a lot of player buy-in for playing in a fun offense, as well as an offense for which UCF could effectively recruit.
3. He actually recruited. GOL was (in)famous for telling kids that the NFL meant "not for long" and that he was only focused on getting them their degrees. Shockingly enough, great athletes didn't want to come play for that guy. So Frost was able to bring in some playmakers that UCF had largely lacked throughout GOL's tenure minus a few diamonds in the rough here and there like Bortles and Kevin Smith (Brandon Marshall predated GOL).
4. He brought in a big time QB in Milton. With the exception of Bortles, GOL never had a particularly good QB. I hate to see how Milton is playing now at FSU...he is just a shell of his former self. Before the leg injury, no one was better at making the quick read, an accurate throw, and extending plays. Perfect QB for the spread offense. I don't watch many Nebraska games, but what I have watched, it looks like he doesn't have a QB. I don't understand why he hasn't been able to move on from Martinez in 4 years.
One concern that was raised about Frost is that he's too much of a player's coach. Basically sees himself as everyone's big brother and would party with the players. Makes it hard to build a disciplined roster, and UCF did have some discipline issues that Heupel had to deal with from Frost recruits. I wonder how much that is an issue in building a Nebraska team that is disciplined enough and mentally tough enough to win the close games they're losing right now.