Writing a programming language is easy, when compared to making an actually useful programming language, which again is easy, when compared to actually maintain

Writing a programming language is easy, when compared to making an actually useful programming language, which again is easy, when compared to actually maintaining and developing a programming language. My heuristic is that the difference in work required is around three orders of magnitude between creation, usefulness and maintenance. That being said, I think every programmer would benefit greatly, just by attempting to write a language.