[javert]

In everyday business, when dealing with dates, the month is usually what you care about most, followed by the day, and then the year (which is often redundant or implicit).

Thus, month/date/years is more "ergonomic" or "user friendly," if one is equally used to either format.

A similar example is time. The hour is usually what you care about most, followed by the minutes, with seconds most often being irrelevant. Fortunately, that's how everyone writes time.

[Dragory]

In everyday business, I would generally start with the day and then follow with the month if it's relevant (often it's not, if talking about a date in the near future), and finally by year if needed. I can't imagine when I'd start with the month, really, but that might be because in Finnish you'd almost always say and write dates with the day first.

As far as date formats go, apart from the ISO format, "21 Jul 2020" is definitely my favorite and always unambiguous. The only downside is that it's language dependent.

[luspr]

I mean ISO. It's lexicographically ordered. And gets more detailed / fine-grained reading left to right. (Year-month-day). I like those features.