I can understand why a lot of people like them all yellow. It is more pleasing to the eye and it is almost ripe so you'll get pretty much all the health benefits.

Perfect ripeness is when there are a few brown spots on the skin. Some people can't eat these because they think the brown spots indicate a brown banana. This is a lie. This is when bananas are perfect!

Anyone who eats a banana with any shade of green on it is doing it wrong.