I think he was mad because I had a huge list of projects with actual due dates, and he mentioned to me he wanted me to look into a tax credit that it was painfully obvious we weren't going to be able to take (as I told him at the time). So I put that off until I got the other work done.
The really frustrating part is that within a day of being reprimanded for "not working hard enough", one of my colleagues called me to say how she couldn't believe I'd gotten a much bigger project done already and how far ahead we were than in past years...
Oh well. I figure he already made up his mind he wanted me out so he was using anything as an excuse. I mean, he literally put me on a PIP for "insubordination" when I asked him the topic of a last minute meeting. I saved the email and check it occasionally just to make sure I didn't actually tell him to "go to hell" or something.