As a teen I could play 10+ musical instruments - ranging from piano to trumpet, violin, etc. Initially I also played by ear, but I soon tired of the trial and

As a teen I could play 10+ musical instruments - ranging from piano to trumpet, violin, etc. Initially I also played by ear, but I soon tired of the trial and error. So I learnt to read music and a some of music theory. With that framework I was able to understand each instrument better and thus structure my practice better - yes, learning scales, fingerings, etc. I would write the score for music I heard and then practice from that. It also helped me heaps to write the lyrics against the score to improve the dynamics, etc.