Not every movie you spend hundreds of millions on will be a hit and attaching specific name's to films won't always drive people to the theater. Yet explaining that to a big studio, they would disagree with you. Even Disney has reaped the rewards of big name movies specifically with the Pirates of the Caribbean franchise. In total all four movies have made just about $3.7 billion and only cost $915 to make and all four were produced by big time Hollywood producer Jerry Bruckheimer.
Bruckheimer built his career on big budget movies like Days of Thunder, Crimson Tide, Bad Boys, Con Air, and Armageddon. He started working for Disney with the film Remember The Titans and the first Pirates film and has gone on to help make both National Treasure films, the remainder of the Pirates films, and most recently The Lone Ranger. Despite the years of success the money printing machine that is Bruckheimer films hit a big wall with Lone Ranger and Disney has since diversified the kind of films they make.
With Marvel, Lucasfilm, and Pixar all under Disney's ownership they don't need the occasional Bruckheimer film every other year to pad out their box office take. With so much potential at the box office Disney announced that they won't be renewing their deal to be the first to produce or pass on Bruckheimer films. I wouldn't be surprised for Bruckheimer films still to come out under the Disney production banner, especially since upcoming National treasure and Pirates sequels are planned. The current first look deal will end some time next year.