He won a Rose Bowl and helped Michigan State rebound from the Muddy Waters disaster but in the end he stayed too long
Well yeah but there was even a cluster**** of controversy surrounding his arrival from the USFL when he lied a couple different times regarding his contract status trying to squeeze more money out of MSU. Essentially MSU ended up having to buy Perles out of his Philly Stars contract plus also buy out his assistants as well (very uncommon at the time) IIRC these 37-38 years later.
(Of course this worked out great for the Stars, who used the money to replace Perles with Jim Mora.)
Also the Muddy Waters "disaster" was in significant part the result of active sabotage and sandbagging on the part of disgruntled Perles boosters on the board of trustees who were bitter Perles had not gotten the job in 1980 and set out to cut Waters' throat from day one.
Waters was put on a nickel and dime shoestring budget guaranteed for failure; his assistant salaries ranked no. 9 in the Big Ten (just ahead of Northwestern which was not operating a D1 program at the time).
Every day of his tenure, Waters begged and pleaded with tears in his eyes for a dedicated football practice building, as Darryl Rogers had before him. The trustees told him to go play in the freeway.
The minute Perles' ticket was punched, the football building started going up.
In fact as I recall the lack of a football building and other budget constraints were the major factor in 1980 when Perles was supposedly a top contender for the job when Rogers bolted for Arizona State a couple weeks before national signing day.
Supposedly Perles had "informally" agreed to the job -- to the point a presser was scheduled, and called off with less than 90 minutes notice -- then proceeded to make several or-else ultimatums, leaving MSU in a panic situation with no coach and in desperation they grabbed loyal alumnus Waters as a last-ditch option.
The pro Perles contingent sat back and said, "sit tight George, you can keep collecting those NFL assistant checks, in the meantime we'll tighten the noose around the football program budget until in two or three years it reaches utter disaster, then we can convince the rest of the board it's time to go big time in football again, open up the checkbook, then you can come riding in on a white horse just as Santa Claus slides down the chimney with everything you want."
The pro-Perles contingent also pushed along this game plan by continually planting preposterously transparent "insider leaks" in the media recounting episodes of the feeble senile doddering Waters supposedly nodding off during games and calling out the names of his college teammates from the 1940s to go in at tailback. At the time the supposedly ancient doddering Waters was 56-58 years old.