Lazzarro

                          Why are Games Fun?
                                   |                  |
  ACHIEVERS <---HARD fun    EASY fun
                                   |                  |
                                  \/                 \/
    MDA AFFECTED STATES   People Factor  ---> COMPETITIVE

What makes people turn off games?

When the balance of types of players is out of balance, when games become unfair.

My opinion:

Lazzaro has some good points, but there is still a long way to go for our understanding of the topic. However I will agree with the two types of fun and with the people factor as every body can share the experience. But there are some games where there is a balance of beautiful complexity and simplicity to it.