Probably the arrogance to write about his "mistake" without actually learning the core reason for the failure. The author starts out owning it, but then shifts

Probably the arrogance to write about his "mistake" without actually learning the core reason for the failure. The author starts out owning it, but then shifts the focus to "we" and other things like execution. In the end I think once KISSmetrics became a hit, it was hubris that took over and the mistakes followed. That's likely hard to own and admit in a blog post, because you'd basically have to be a different person to write it. So to me, the "ugh" response makes a lot of sense.