I am a manager and would generally say that I am very tuned in to what is going on in the office and with my staff, and over all I do a very good job at hiring people. It is important to me not just to find someone who is capable of doing the job, but also someone who compliments the team dynamic.
I had hired this one woman who worked with us for almost 2 years, during that time although I knew she could be very direct and abrupt at times, I liked her and got along well with her. Based on my observations, I knew she could annoy the others from time to time, but over all I thought they all got along.
I had it totally wrong, when she resigned to go to another job I have never seen the team so happy for someone to leave. There were no good-byes or any well wishes at all. They could not stand her. I am still surprised at my for not seeing it for what it was.
For myself, I have to say I still liked her, but maybe my overall view of the situation was clouded by that.