On that note, have there ever really been any good threequel comic films?
We all know SM3's flaws. X-Men 3 was a badly-paced, character bloodbath that was also tonally off compared to the first two films (no doubt without Singer at the helm). I see lots of complaints about Dark Knight Rises (I thought it was great, but it's still the least of the 3 films), and Iron Man 3 also gets a lot of online hate (I liked it loads better than the 2nd myself).
Is it just that people get so tired of these franchises by the time of a third serving?