Annoyed Doctor

I have a doctor who is annoyed, reducing the department's prestige but I have no idea why. His traits are Pleasant, Hard Worker and Diagnostic Genius so it's not that.
That is his only negative satisfaction, the others are all positive.
Anyone have any ideas?

Hi i have simillar problem. Staff with hard worker trait dont take breaks. If there is a lot of work they stay in office even if their needs are low. So they work even hungry, thisty and exhausted.

This trait makes them work for a longer time but in the cost of their needs.