The design of the left one is complete and integrated in every sense. Ostensibly the right one should be equally good as they are very similar -- but they are not. The right one seems to have suffered from middle age spread, the bloated dustpan shares little relationship with its brush. The handle seems disjointed. Gone is the matching hole in the handle of the dustpan and the brush that clearly announces the joining of the two. The white extension of the brush handle on the right is visually isolated from the black handle and raises the question of where the handle ends. This design asks questions rather than answers them.
Interesting how two ostensibly similar objects can be so different.