This could just as easily be written as, "Why doesn't enterprise software work?" If you're just paving cowpaths, you're not getting the best out of any technology improvement.
The best cases of improving enterprise business is when the project is driven by a respected line manager, who can challenge people to make tough decisions. These are frequently managers with CS or technology backgrounds who have migrated over. It can't be a, "Put this person on the project because they're not useful elsewhere." It has to be, "Put this person on the project, because it's the only way to guarantee it'll succeed."