Would your employees say you are mostly upbeat, mostly neutral or mostly negative?
The important word here is 'mostly'. It could mean that you are intentionally behaving this way or it could simply be a habit.
If it's intentional and you're mostly 'upbeat' then you don't need to read this Fast Company article - but you should anyway to get affirmation!
If you are not aware of how you 'mostly' are, or you're mostly negative or neutral, then PLEASE read this article. You'll be a better manager if you act on the science related suggestions.
Why positive encouragement works better than criticism