Why do I need something on all of the time when I am not lookng at it?
Because it looks nice that way, to you and perhaps others around you?
You would not have to worry about needing to turn it on when it's not at the ideal angle for it.
There is no way for the Apple Watch to know you are looking at it.
Technically it's possible to make a device that can do that, but it would be REALLY hard to incorporate that technology in a watch.
Would be interesting if your TV at home only turned the screen on, when you sat or stood in a certain position and the rest of the time it turned the screen off to save power, so if you just glanced at your TV, perhaps from around the door, or across the room the screen was blank
As I say, let's be honest, it's a limitation we have just accepted at "The Norm"
Also, let's be double honest. If due to some amazing screen or battery tech, the Apple watch was on all the time, unless you wanted it to be off, but lasted just as well, on all the time.
And then say a Samsung watch had to turn off after say 10 seconds of not being touched to save battery and acted just like the Apple watch will.
Everyone here would rip the ass out of Samsungs watch for having a black screen almost all the time.
Unfortunately, as I say, it's a limitation, we all have to live with, no matter what make.
Unless if course, you also have incorporated an additional layer on the screen that was LCD or E-Paper or something that could be on all the time, and only the full colour screen coming on when you needed to do more.
I'd like to see that done well.
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You don't have to hold it up to turn it on... It uses the built in gyroscope to measure that you turned over your arm and turn on the screen... So you can still use it "discreetly"
it's an interesting idea, though I suspect very hit and miss.