Our introductory programming course at university used ML and I didn't like it or get it. I already knew some C++, BASIC and Java and was mostly interested in real time graphics programming and the kind of examples used in the ML course were not interesting to me and I didn't see how it would help me tackle the kinds of programming tasks I was interested in.

I found recursion pretty unintuitive and didn't find the way it was taught in that course worked for me. At the time it mostly seemed like the approach was to point at the recursive implementation and say "look how intuitive it is!" while I completely failed to get it.

Many years later after extensive experience with C++ in the games industry I discovered F# and now with an appreciation of some of the problems caused by mutable state, particularly for parallel and concurrent code I was better prepared to appreciate the advantages of an ML style language. Years of dealing with large, complex and often verbose production code also made me really appreciate the terseness and lack of ceremony of F# and experience with both statically typed C++ code and some experience with dynamically typed Python made me appreciate F#'s combination of type safety with type inference to give the benefits of static typing without the verbosity (C++ has since got better about this).

I still struggle to think recursively and my brain naturally goes to non recursive solutions first but I can appreciate the elegance of recursive solutions now.