[andreyf]

Consistent choreography. Do: Direct user attention with coordinated, orderly motion. Don't: Don’t confuse users with inconsistent or disorderly motion and objects leaving/entering in seemingly random directions.

This seems like a strange hard rule to follow. The disorganized demo has a very different "feel" to it that might be appropriate in some places more than others.

[matchu]

From my viewing, the "feel" is chaos. Why are they all moving different directions? Does it mean anything?

Watching the Don't video legitimately hurt my brain; the only way an app can justify that kind of choreography is if disorientation is an intended part of the emotional experience.

[ImJasonH]

The "Don't" video looks like billiards balls on a break, which might be the feel certain apps are going for, particularly games. It doesn't make sense for a productivity tool like Calendar, obviously.

It's also just a guideline, a suggestion, and if you think your app would benefit from having items fly in and out in all directions, if that's the feel you want to give your users, that's your choice. It's just probably not the right choice in most cases.

[andreyf]

"Chaotic and fun" is how I would describe the feel. To me, the orderly one seems relatively boring.