Pitcher mound is a result of trial and error in order to find the perfect distance and height that will be some kind of point of equality so the pitcher and the batter won't be advantage on each other and ensuring the attraction of the game.
It is because we don't want a game when a pitcher is always striking out players and on the other hand we don't want the batter to do a home run in every bat.
First a little bit of history..
How the pitcher's mound was born?
In the early days of baseball , pitchers were required to stay within a pitcher's box that had its front edge 45 feet away from home plate. But pitchers were dominating batters, so in 1881, the front edge of the box was moved back five feet.
But this was still not enough, so in 1887, a new rule required a pitcher to keep his back foot on a line that was 55 and one-half feet from the plate. Finally in 1893, the pitcher's box was removed, but the pitcher's plate, or rubber, was...