If you play 4-5 hours starcraft 1v1 everyday you memorize mouse movements with your cerebellum. it control muscles and memorise sportive moves.
a computer player generally uses mouse clicks with fingers and wrist moves.you cerebellum will recognize their precise location when you need them.
if you make practise everyday you play fast ,micromanagement needs fast clicks.Easily you become a gold lvl players.After that level you need some strategy also it comes with experience go watch some replay 1v1 then you learn more.If you are good with strategy you can play 5-6 hours a day and there is a possibility to become a gosu if you have talent.
Not everyone has the ability to practice for that long due to their jobs or kids, so that's why I am offering my coaching services. Help them out with what's constantly killing them and help them see what they need to work on.