Why do people like playing games?

There are many reasons why people like playing games. 1. Games are different from real world and hence players can usually do/achieve a lot more than what they can do in the real world. 2. Games give quick results 3. People/players can feel less responsibility (e.g. players can just quit the games if the games do not go well) 

However, because of these very reasons, games also have side-effects such as making people be less responsible, want more quick responsive answers, and not be able to discern between real world and game world, etc.