What makes you believe that humans can't multitask? I can move both of my hands at the same time, or rub my belly and pat my head. Both of these examples are m

What makes you believe that humans can't multitask? I can move both of my hands at the same time, or rub my belly and pat my head. Both of these examples are me performing 2 functions simultaneously. I can do these because basic motor skills have become a trivial task through my years of development. Just like muscle memory, which can be highly developed in professional athletes, I think many tasks can be developed to the point of being able to multitask (like when someone says something becomes 2nd nature, or natural reaction). As others have mentioned, I don't think multitasking is a proficiency in itself, but rather when you become proficient enough at a task your brain can internalize and multitask it.