If your name is Guillermo del Toro or Steven Spielberg, acting as an "executive producer" on a small film or even just somehow being associated with it gives it a type of credence and name recognition that no ad dollars can buy. Would 'The Orphanage' have gotten any traction without del Toro's name attached? Maybe not, and that would be a pity because it's a damn fine little ghost story. Of course, this can totally work against the film if it's someone like, oh, M. Night Shyamalan.
If you went to see 'Scott Pilgrim vs. The World,' you probably also saw the trailer for 'Devil,' which is "From the Mind of M. Night Shyamalan." Chances are, you also heard the infamous boos that accompanied this message. Never mind that 'Devil's connections to Shyamalan are only that he came up with the story and that he's a producer; marketing 'Devil' with his name might be the kiss of death. People were pretty worked up about 'The Last Airbender' and its casting process, and he didn't do a really great job of defending 'The Last Airbender' against charges of racism. Others just think his career going down the toilet. Plenty of pixels have been spent arguing about M. Night Shyamalan.
Far less have been about 'Devil.' Is it simply because Shyamalan is associated, or because the trailer just isn't appealing? Even the trailer that showed up on YouTube (and has since been removed) was filled with anti-Shyamalan comments. As Erik Childress wrote, "The filmmaker once ridiculously dubbed the next Spielberg now instantly taints anything he comes in contact with as reactions to the 'Devil' trailer show."
Are you going to see 'Devil' despite M. Night Shyamalan's admittedly small role in its development? Do you think its association with him has tainted it? Or are you going to go and find out which of these people are THE DEVIL?!