Legacy system conversion projects are always challenging. Rollout strategy can make a huge difference in successful user adoption and overall project success.
Only when I began writing them down did I realize that I had recurring dreams. I had believed that my dreams were largely random and varied, but instead I learned that I had many frequently recurring themes. Similarly, the process of writing down my thoughts on software development has shown me that there are also recurring themes.
One of these themes is the impact of rollout methodology on a project's success. More specifically, rollouts of legacy system conversion projects. Rollouts of brand new systems into an organization are typically less painful, as you are often automating a paper process, or inventing a new process that improves productivity. However, legacy system conversions are almost always painful, as there are many processes that have emerged around this system. People have developed a form of muscle-memory with the old system that even they themselves scarcely understand.
We have successfully replaced dozens of legacy systems where everyone was happy and all was good with the world. But it's not those projects I want to talk about. I am going to talk about the projects where things went awry, because I don't want to make the same mistakes again. Hopefully, these words will also help the reader to avoid similar problems in their projects.