Well, reading a pattern can sometimes be tricky. I wish that I had seen the left front of my sweater before completely undoing it. It turns out that I didn't read it incorrectly, but I was looking at the portion incorrectly. So I undid everything and then realized that I hadn't made any mistakes. I thought it started at the button spot, but it actually started at the bottom of the bolero, so I was looking the portion completely wrong.

Lesson: envision the pattern before knitting it; diagrams help; be careful!