How come most Game of Thrones mashabiki don't like Grand Maester Pycelle?

He is quite an amusing character, and in a way I hope that he doesn't get succeeded kwa Qyburn, who is a far darker and creepier character. He's probably hated because he's a faker, appearing to be a wise old geriatric maester, who gives sage advice, whereas we know him to be lively enough to have sex with prostitutes and always plotting to undermine the likes of Tyrion and Varys and to further himself.
He is quite loathsome, but the same qualities make him a good character who I also enjoy seeing in the story.