When it comes to performance at gaming, if you strive to improve, you'll eventually reach some physical barriers. These are sadly caused by the limitations of our weak mortal bodies.
At some point, you'll encounter situations where you need to consider if the current situation allows you to blink or not. Based on a quick search, the average blink takes 100 milliseconds. That's way more than enough time to make a fatal error. When it comes to rhythm games, the notes might even be off the screen before you're done blinking.
This is the typical saying of "blink and you'll miss it" taken literally.