In the 3000 community a major manufacturer is making its way off its ERP system. It will take years. We've been told not to say who, but the more important element of this story is the what. As in, what not to do to make a clean move away from applications that drive finances and manufacturing.
It's been a struggle, but mostly due to poor project planning and project management. Migration partners who've served the 3000 community pride themselves on the planning deliverable. Without such good planning, "it's taken significantly longer than they thought it would, primarily because they chose to ignore warnings."
The top IT management refused to perform any business process analysis before beginning the project. Business processes have been traced by MPE/iX applications since the 1980s. The software has been lauded for bending to the needs of processes, instead of the other way around. "They knew what they were doing, and didn't think we understood what it would take to implement new systems in our businesses."
Planning comes at a discount as well as with a price. You get the discount when you plan. You pay the price when you don't. Especially in migrating from a legacy system ERP, where the P stands for Planning.