Yes, it is easy to tell other people to just focus and not let that sinking feeling affect your performance but there are just some cases where the feeling is too hard to swallow.
What if the company you work for tells you there is a chance a few of you in the department will be laid off? Sucks, right? Considering how hard it is to find a good paying job that satisfies your definition of a good paying job, it can give you a ton of stress.
It gets only worse if how it was told to you was inappropriately handled. If the higher ups say the real deal is that there really is no confirmation yet if such thing could happen. How would that make you feel? Worse, right?
In the first place, why would they open that up to everybody? Every single day one goes through it not knowing the outcome.
If you were going to be in that position, how would it make you feel? Low morale? Or just no care at all?