I suspect what they do is come up with their own definition for discipline.
I know a woman who writes faithfully every day and has published over a dozen books. But I know another woman who writes in feverish 15 or 18 hour marathons only stopping when she cannot stay awake any longer. She also has around a dozen books.
And of course “get published” is subjective nowadays, too. Lots of self published authors are making a living without an agent or publisher. And lots with traditional publishers that never crack 500 books sold.
But I do think you’re on to something. Maybe we just need to figure out what discipline means by our own definition.
Also, I have needed a slap to the head on occasion. When that doesn’t work, a brick to the head usually does. :)