Vim reasons I'm guessing
inoremap jk <esc>
("jk" doesn't normally appear in English and is easy to type)Unfortunately 90% of vim interface implementations don't support it.
$ aspell --lang=pl dump master | cut -d / -f 1 | fgrep jk | wc -l
981It bugged me terribly at first but I liked it once I was used to it.