Barriers

These words, ascribed to Beethoven, are an eternal truth etched in stone.
Many people, after they've reached the limit of what they thought they could say or produce innovatively, have continued to press forward into chartered territory and, in so doing, have extended their creativity and brought into existence many beautiful and useful things that would be non-existent otherwise.
A great many splendid works of music, not to mention an avalanche of other stunning works of art, were generated this way.