That’s a clunky way of saying “when something is different, make it look different.” The best designers, in my opinion, take this to heart and don’t use too many variants to make those differences as clear as possible.

What does OLED black smearing look like? In this example, the dark grey square seems to be lagging behind the light grey square, but they’re locked together. (Needs to be viewed on an OLED screen.) pic.twitter.com/WYFEXKAvsG— Marc Edwards (@marcedwards) October 20, 2018

Apple Watch—Series 3 Digital Crown