> Yeah, because people usually compile their programs before running them.

The developers do, yes; with Javascript, they don't have to worry about compiling for multiple platforms like, say, a C developer would, they could even just ssh into a server and edit a single text file while everybody across Windows/Linux/MacOS/iOS/Android/etc can run the new version as soon as you save the file (mod browser compatibility issues, of course). I think their point was that Javascript is the only language that can do end-to-end simplicity like that.