For example, I really can't afford to program with any JavaScript language except ES2015 - I just don't have time to try to understand all the weird idiosyncrasies and underpowered crap that is older versions of JavaScript - I need to work with "JavaScript that makes sense" i.e. ES2015. But to do that I need to be able to wrap my head around - and fight all the myriad problems with - getting my ES2015 to compile using the webpack babel toolchain.
It's a strange thing about programming that to understand the easiest way to do it you need to have a higher order understanding of the entire programming system that you are working with.