This article began life as a talk I gave in late 2024. I love formal methods—I should say that to begin with, because this article is mostly about what doesn’t work when trying to do FM projects. Over the last 20 years, formal methods have grown and grown, and I’m proud to say that Galois has made its own contributions to this success. I made a lot of mistakes when I was scoping and running formal methods projects. I’d like other people to avoid the pitfalls I fell into, and hopefully make bigge...