Let's take music as an example. In the reminiscence of everyone's music careers stands a point in time when they revelled at the fact that through mechanical repetition, they were able to "play a song". What makes them pale in comparison to the "professional musicians"is that for the most part, it is because the professional musicians have devoted more time to practice. Not mechanical "playing the notes" practice but "deliberate practice".
Deliberate practice is extremely complex so I will unambiguously unravel it. Intrinsically, it is not only practicing the notes, but looking at the greater picture. It is studying every nuance in a note, perfecting that nuance, then moving on. It is perfecting a series of nuances, and forming a shape. It is using those shapes, that you form a piece. Slowly conjoining the separate parts which have been perfected. This is not all though, for if you are determined to make your piece flawless, there is no doubt that it will be. What gives these "brilliant" musicians the extra edge is that after strenuous, prolonged, and mind-numbing deliberate practice, they inject their own emotions into the piece. The piece then changes. It is no longer only a long list of notes, but a story. Told through the eyes of the musician. This is a mentally exhausting process, but I still don't understand why I have to do it for beethoven's pieces though. After all, he is deaf.
So, if you really take the time to let these thoughts linger in the back of your head, you will understand the title of my post. Everything is easy to do. Nothing is easy to do well.