Learning the piano is sort of like a teenager getting braces. For a few years, the teen's parents pay  a lot of money so their child can either fix his or her teeth, or learn the musical notes.  The student typically ends up fibbing about what he or she didn't do but was supposed to do (putting rubber bands on their braces, or practicing their scales). This can be an unhappy childhood experience.

But while everyone grows out of braces, some people never recover from unhappy childhood piano lessons. This is, in part, because a true pianist's brain is actually different from that of everyone else. Take the guitar and drums, for instance. Drums are functionally pitchless and achordal, so pitch selection and chord voicings aren't part of the equation. Guitar only allows for six notes at once and heavily favors left-hand dexterity. But piano is the ultimate instrument in terms of skill and demand: two hands have to play together simultaneously while navigating 88 keys. The hands can play up to 10 notes at a time.

To manage all these options, a pianist has to develop a totally unique brain capacity, and that is the goal of learning piano even from a very early age.