Number 9, "Poor Validation," links to a discussion that encourages a fad that I can't get behind: namely, don't disable the submit button. As a long time Mac user, my understanding has always been that you should not allow the user to do anything you're going to flag an error for.

In the discussion linked to, the example given falls apart in my mind because every one of the fields pictured omits placeholder text, and the placeholder text could easily say "Required." (That's just one solution.)

https://twitter.com/vponamariov/status/1400388907401977857

I could maybe see a counter-argument in the event of a long form. But I would say that long forms may, in most cases, be a bad idea in the first place.