Only a few friends had Atari computers when I was a kid. The one thing that stuck out to me was it had a Help key but most programs told you to press 'H' or some other key for help instead of the Help key, which makes me wonder if knowledge of how to detect that key wasn't in the manual? Atari owners were passionate about their computers and seemed happy with them but at least in my little town, there just weren't very many of them.

The first 400 and 800 did not have a help key. As such if you used the help key you either had to refuse to work with the large installed based of those earlier systems, or you had to provide an alternative. The alternative won in most cases and then it wasn't seen as worth also supporting help (remember bytes mattered)