Quote Originally Posted by GoktimusPrime View Post
It's also dependent on what people are willing to buy. Hasbro keeps on using the same tired-old characters ad nauseum because they know it sells, especially Optimus Prime.
I think it is also because the same old characters require the least amount of effort in advertising. Optimus and G1 has heaps of history and advertising behind it. A new Transformers series and new characters requires effort (=money) to get to a likeable level.

Optimus has that in spades for free!