i know exactly what you mean what helps me is forcing myself to perform or show my work to other people thats how i learned guitar got better at making beats and am starting to learn how to program robot stuff me telling people ill show them motivates me to really go for it because i dont want to emberass myself trust me shame is a great motivator i still dont really master anything because then i lose focus but im pretty good at a couple things now  this takes some courage but its better than hating yourself over a lack of skills