This is basically legend now but there really was a time when Disney focused on original work. And this wasn't just because they were young. They actively avoided doing the same thing more than once. It all came from Walt's tendency to get bored with repeating himself.
The Three Little Pigs sequels are great cartoons in their own right. Disney rarely made flops at the time. But the sequels aren't a huge step forward from the original, and you can tell they were only made because Disney felt they had to do SOMETHING to capitalize on the original cartoon's success.
But Walt could tell these sequels weren't lighting the world on fire. This only justified his "no-sequel" philosophy. He walked that walk though. He never made feature film sequels (even though he had so many opportunities) and he kept breaking ground through his life. Like producing live action films, or nature docs, or theme parks, or whole cities (not enough time for that last one tho)