Studying human behavior is just very difficult for any science (psychology is just at the fore). E.g. in programming languages, there are researchers that are trying to figure out how to empirically study human performance in relation to various programming features. It is quite difficult to get meaningful results, and experiments are expensive (you can&#x27;t just put people in a box for later use!). No wonder most PL researchers focus on machine performance and theory...it is just easier that way.