PoP Project is a tool bred to be simple. When the first UI was conceived, it was simple. Yet we found ways to make it simpler. Then when this redone UI was simple we scrutinized it again to make it even simpler. We played the tune of simple several times on PoP Project, and every time we were very pleased with the results. Our private betas were very happy with how simple our tool felt, and each redux made them happier. However, they understood the game and now are in league with our efforts to make our tool simple.
This is how great UI is born.