Only the composer is able to play it right if anybody

This thought came to my mind today at the musical lesson which I attened this morning. I accompanied my son which was taught by his musical teacher.
and I thought attentively listening to the sounds of piano that all the pianists when playing a composed by someone else music are only trying to guess the true meaning the teue pattern and sounds of it and ubevitable fail. I only guess if the composer itself could succeed in bringing up the whole idea. What if they were doomed to desperatly spoil the underlying powerful insight to the nature of things?!