Michael found a nasty one to start off the week with the story of how an ERP install gone bad eventually killed a maker of specialized emergency vehicles.
In the end, stupid customers are much more susceptible to being on the sharp end of the stick when they are unable to properly manage a project internally. When I did web development work, we used to have a saying: A website is always reflective of the organization it serves. Almost always a poorly organized client that lacked direction would end up with a website with the exact same characteristics, no matter how hard you tried to save them.
In the end, trying to make a flip-of-the-switch transition from their old ERP system to a brand new system was more or less a recipe for pain. They would have been better off continuing to use/lease the system from their parent company while they slowly implemented new systems to address specific needs, and in the end they would have had their brand new fully independent ERP system.