Isn't Man of Steel a 55 on Rotten Tomatoes?
Yes, I said I want to use the average critic rating because it is accurate and reliable. The percentage score only shows how many positive reviews critics on the site gave to the movie and is not very useful (a "positive review" is a very vague concept, don't you think?).
Let me explain with an example. The movie "The Anon from Another World" is reviewed by 10 critics on RottenTomatoes. All of them like it because the anon monster dies a horrible death at the end of the movie; therefore the movie has 100% tomatometer score because each one of them gave it a positive review. "Positive" is a vague concept in this case: let's say that 5 critics give it a 75/100, 3 critics give it 7/10 and 2 critics give it 3/5.
The ratings are nice but not awesome because the movie focuses too much about how the Anon is despicable and there is a little plot hole about how one of the characters could have survived the first Anon monster attack.
Since the Tomatometer shows the percentage of positive reviews its score will be a whooping 100 % and everyone will think "OMG THZ MOVIE IZ THE BEST CANT WAIT 2 WATCH IT". But really there is little substance behind that apparently perfect score.
The average critic score (which no one reads because the unreliable tomatometer is so darned big) instead will show that the "real" appreciation by the critics is 6.8 thus earning it "only" the Decent Movie category here. There is a huge difference between the two scores, don't you think?
Here is the Man of Steel rating on the site:
As you can see the tomatometer isn't even reliable to see if the majority of the critics liked it; critics giving it a fresh status are more than the ones saying it is rotten but the tomatometer still defines it as being rotten overall.