If you're stopping to look what button to click next you're clearly a button mashing baddie, and probably backpedal. So I want to go through my rotation; I don't have to stop and look to know that my first set of keys I press are 4-1-2-3-1, which is all from instinct(flawed use of the word btw) and training. Chain macroing doesn't speed up the action, chain macroing allows you to go through the entirety of the rotation with minimal effort, and allows for someone, despite using less thought and exerting less effort, to overcome someone actually playing the game without this pseudo-automation.
Macros give one person the competitive advantage; they play a huge portion of the game, you know, that whole giving the game input part, for you. Congratulations, you can click on the target and go on autopilot from there