All starters ranked by design

By design. therefore you would expect a starter to be designed differently (or perhaps not the best) in comparison to its further evolutions. E.g. Blastoise should be the best looking when compared to Squirtle and Wartortle, although it is not in my opinion.

Credit to https://bulbapedia.bulbagarden.net/wiki/Starter_Pok%C3%A9mon for the images.