The problem I had with nano is that, for the time being, it was supposed to be easy to use. With that in account I always get lost when saving a file and closing the thing because one’s used to doing something else with Ctrl+O and Ctrl+X.
Whereas with Vim (and Neovim for a little while, and now with Vis) I knew it had a steep learning curve from the start so I always had it in mind. And all the funny stories about quitting vim.