Year-Month-Day best everywhere

Facts. The sorting system for files inevitably makes YYYY-MM-DD more optimal. I tried to resist but it doesn’t work.

To the commenters justifying the written form MM-DD-YYYY on the basis of preferring to say the name of the month followed by the day (which the written numerical sequence does not preclude you from doing). If someone were to say something like “the time is a quarter to eleven” do you think they would have a case for writing it 45:10? And if so, how would you deal with the ambiguity of “ten past ten” if they wrote it 10:10 instead of 10:10?

This is big pp idea and I like it.