in no particular order:

1.  He whined to the NCAA, without cause, merely because Billy D. had the audacity- the audacity! - to recruit a player in the midwest that Roy felt he was automatically entitled to sign to Kansas.

2.  Because he also sicked his fellow unc alums on Donovan.  

3.  Williams violated NCAA rules when he was at Kansas by permitting bosters to provide illegal gifts to his players as incentives.

4.  He looks like Huckleberry Hound but lacks the integrity or depth of said cartoon character.

5.  He frequently refers to himself in the third person, and it's a cheesy reference to boot ("Ole Roy").

6.  He curses at reporters but never gets called out for it.  At least Krychokeski gets called out for his foul mouth.

7.  He cost millions of Americans their hard-earned bucks over the years in bracket pools with his frequent early tourney flame-outs at Kansas despite getting cushy seedings.

8.    He played for and now coaches a team with effeminate colors and effete fans (talking the male fans here).

9.   His national title came in a tourney when he should have been sent home, but in a finish that marred the integrity of the tournament his team's foul on Villanova in the waning seconds that would have sealed he deal for Nova was instead wrongly and suspiciously called a travel/no basket on Villanova.

10.  Because he had the two-faced temerity to wear a jayhawk button to the title game last year as though that would make up for screwing over kansas and its fanbase when he bolted their job for north carolina.