Mariah Carey - Mariah takes the word diva to another level. According to actor Rob Huebel, she once arrived to a movie set four hours late and refused to sing a song she was hired to sing.
Nicki Minaj - From 'American Idol' beef with fellow judges to an angry tirade at celebrity facialist Dawn DaLuise, Nicki Minaj is trouble at work.
Lady Gaga - Assistant Jennifer O'Neill said Gaga doesn't like to sleep alone, so she had to sleep with her all the time. O'Neill sued the singer for nearly US$400k of unpaid overtime.
Sid Vicious - The Sex Pistols bass player was known for his struggle with drug addiction. His erratic behavior both on and off stage made him a pretty difficult person to work with.
Syd Barrett - Pink Floyd's former band leader suffered from schizophrenia, exacerbated by drug use. He'd be all over the place at live performances as well as during rehearsals.
Charlie Parker - Bird was an outstanding jazz saxophonist, but he was also an alcoholic and a drug addict. This, of course, made him unreliable onstage.
David Ruffin - The Temptations had to endure David Ruffin's unpredictable behavior. He'd show up late to rehearsals and refused to travel with the group.
Mick Fleetwood - Fleetwood Mac's drummer admitted his unpredictability onstage. "There's no discipline," he said. "I can't do the same thing every night."
Frank Zappa - Frank Zappa was a nonconformist when it came to the music industry, making him very hard to collaborate with. Zappa actively avoided making a "commercial hit."
John Frusciante - The Red Hot Chili Peppers guitarist quit the band when his drug addiction got in the way. Working with him became unpredictable and unreliable.