I failed my stage I yesterday. Pissed me off to no end. Our chief pilot did it, and everyone dreads doing rides with him because of the way he thinks. He's extremely technical, and I basically failed it because, even though I was within PTS, I was chasing the altimeter within 100 feet of my assigned and couldn't get it trimmed. While he can't fail me on that, he's really not interested in seeing me repeat what he could fail me on, which was a botched NDB procedure turn. I forgot which heading I started on and therefore couldn't find the reciprocal when I came back around. Legitimate, but he knows I can do it and I knew what went wrong, so he's not even sure we're going to do it again on the retake today. I realize that failing a stage check isn't that big a deal, but for me, personally, it's huge.