Experience is Queen

We are creatures of habit. Habits automate decisions for us so we don't have to spend time on them. If there's a lion running toward us, we run. If we build a new web application, we use the layered architecture style. We have done it so often in the past that it has become a habit.

I'm not saying that this is necessarily a bad decision. Habits are just as good at helping us to make the right decision as they are at making a bad one. I'm saying that we are doing what we are experienced in. We are comfortable with what we have done in the past, so why should we change anything?

So, the only way to make an educated decision about an architecture style is by having experience in different architecture styles. If you are unsure about the hexagonal architecture style, try it out on a small module of the application that you are currently building. Get used to the concepts and get comfortable. Apply the ideas in this book, modify them, and add your own ideas...