A function has a well defined scope, parameters and output. A comment does not. A function name describes an intention. Within the scope of this function, someone can check whether the intention is respected by the implementation. If this function calls other functions, just assume that they are working as their name suggests. If that is not the case, fix those other functions later.

This has been my overall approach to maintaining code. To such extent that I design things around the possible names I can find. Some call that DDD. I call that respecting my team mates. Without writing and naming function, this is not possible.

Languages such as J and K are fine for single developers & prototypes but really bad for bigger projects.