I think you mean "Why the hell do Americans frown on passive voice?" ;)
I blame the early MS Word grammar checker which always called out passive voice as poor style. :P I'd imagine it was written that way because passive voice was easy to detect, and corporate power posturing tended to paint passive voice as 'weak'.
That said, passive voice is also associated with weasel wording and evasiveness, so if you're trying to communicate clearly and directly, it might not be the best way to phrase things.
I suspect Elements of Style is at the root of "avoiding passive" being popular advice.
It's a decent rule of thumb for those of us who accidentally slip into writing in the passive. Too much passive leads to writing that feels less direct, less active. Alas, as with every rule of thumb, you will get people who take it as a commandment and loudly denounce any and all use of passive, thinking they're being clever. I worked with a tech doc writer who liked to point out passive voice usage in peoples' work emails. Whatever gets you through life I guess...
I blame the early MS Word grammar checker which always called out passive voice as poor style. :P I'd imagine it was written that way because passive voice was easy to detect, and corporate power posturing tended to paint passive voice as 'weak'.
That said, passive voice is also associated with weasel wording and evasiveness, so if you're trying to communicate clearly and directly, it might not be the best way to phrase things.