Isn't the fact that darkness effectively disables one of your most important senses, so that you can't tell what's going on, enough of an explanation? Aren't y

Isn't the fact that darkness effectively disables one of your most important senses, so that you can't tell what's going on, enough of an explanation? Aren't you (as I know I am) afraid of writing code that you can't test, for example, despite our hominid ancestors' lack of computers?