The notation of a tune is like a pencil drawing of the music,it gives you a good place to start to learn a tune.After learning to play the tune from the dots you start to colour the music adding light and shade
to bring it to life. A good analogy would be reading a story in a monotone,all the words would be there but the rendition would be dreadful,the skill is in the use of emphasis and tone of the voice,a good reader can give a truly memorable performance.
I once heard a classically trained violin player comment on a Irish traditional player,his technique is not technicaly advanced, what makes his music so good is he is playing with his heart.