Another interesting point is that the players in Minecraft, especially children, love this game because of its inscrutable. Schoolchildren and teenagers love Minecraft because of not so user-friendly interface and the absence of adequate explanations. Minecraft is incredibly complex, but when you start the game you don't get any tooltips that explain what to do in the game, there isn't even a "Help" section. You simply have no other choice but to learn the game on your own.
Such approach is at odds with most modern games which explain to you how to move, look around or shoot. In Minecraft no one will explain to you what a skeleton can kill you, or that if you dig too deep into the ground, you can stumble on lava (which kills you as well), or even that you will have to craft yourself a pickaxe.
The reason for this is quite prosaic: in the very beginning of the development of Minecraft, the developers simply had neither the funds nor the time to add any tutorials into their creation. And this accident turned out to be one of the defining reasons of the Minecraft success. Ironic, isn't it? Players really have to learn how to play, discuss new ways and tactics of survival in school or at work, create forum topics or even whole wikis (the largest of which contains more than 5 thousand articles). Produced even entire books-tutorials on Minecraft. Minecraft is not just game, now it is a real cultural phenomenon. It is clear why it is being sold with such incredible speed. What other game can boast something similar?