I get annoyed when things don't go as planned. Mirny likes to tell me that's my best personality trait - which says more than a little about what he thinks about me.
It's certainly not helpful in my line of work. In the startup world, things don't go as planned all the time. You promise one thing to your investors, and two days later your engineering lead is calling you up and explaining that they'll need a year and ten more developers to deliver it. There's nothing to do then but sigh, count backwards from ten, and start thinking of how to spin that as disrupting the budget industry.