Expected display to be bright when navigating menu, am I wrong?

I asked about an adjent topic in another thread about the screen brighness on my 970. But I just have to ask: 

When I press a button to go into an activity or entering the menu something else - my screen goes from completely turned off to a very very dark menu/screen. I expected the screen to go into full brightness when also entering the menu. Was this wrong? Or is this part of a buggy devices?

In the other thread I explained that I have issues also with screen staying dark when turning my wrist and trying to look at the time.

Is there a way to force the screen to wake up? Right now i have to shake it really hard and sometimes it wakes up, but it seems very random for me when it decides to be what i would assume is normal brightness and when it is really really dark.