The perfect game is indeed a rare and special occurrence. It's true that the unassisted triple play is even rarer -- only 15 in major-league history! -- but it's more the result of being in the right place at the right time. The perfecto, on the other hand, is a grueling, full-game gauntlet where the pitcher and his fielders must be absolutely locked in and, yes, get some good luck along the way. In the long history of the major leagues (which I date back to 1871, but others prefer 1876), there had been only 23 perfect games.
Now make it 24.
Huge congrats to Domingo German of my beloved New York Yankees for twirling the fourth perfecto in team history!