Is there a reason you don't simply put them on a virtual desktop and switch to that desktop instead of turning your head to look at a different monitor? Maybe

Is there a reason you don't simply put them on a virtual desktop and switch to that desktop instead of turning your head to look at a different monitor? Maybe it's my slightly lowered perception threshold, but having a screen in my peripheral vision where e.g. new emails could be seen wouldn't be useful: I'd still see that a new email has arrived and would still need to decide whether I want to look at it now or whether that can/has to wait. And that's only a small step away from having a popup notification on my main screen about a new email.