Focus on the right stuff

Why is it that we, ok, I keep on focusing on the wrong stuff. I held a short 40 minute seminar this week on Team Dynamics and The Five Dysfunctions of a Team. Directly after I rated my performance as ok but not more than that. It could have been more passionate, I could have been more snappy and I could have been better... as always of course. Then I read the evaluation forms... I shouldn't. On a scale of one to four 25% gave me two, the rest gave me three or four. Which part did I focus on? The 25%! My "ok" took a huge fall down to "crap". Luckily, my team mates did not let me crash and burn and instead pointed out the fact that at least 75% actually got something out of the seminar. Thanks guys!