2. 'Caddyshack II'
When even Rodney Dangerfield refused to come on board for a Caddyshack sequel, the studio should have realized they had a problem on their hands. Instead, the hired Jackie Mason, Randy Quaid and Dan Akyroyd and plowed ahead with another movie about slobs battling snobs at a golf course. Chevy Chase returned, but that man doesn't know the word "no" and even he later said it was a mistake. Harold Ramis did co-write it, though he later asked the studio to take his name off it. He changed his mind when they said it would cause all sorts of negative press, but the film had bigger problems and it totally tanked.