If you want to sell a lot of stuff, you have to be able to replicate your product. There's 4 main categories with different levels of replicability.
This is where your product is selling code. Like software. It can replicate extremely fast.
This is where you create media. Like videos, or articles, or VR experiences. It can replicate extremely fast because it's delivery is based on code.
This is where your product is a physical product. Like a book or car. You can make a bunch at one time then sell them all.
This is where your product/service goes through people. Like a marketing agency or team of lawyers. This is more complicated to replicate, but often has the biggest moat from competition.
P.S. This is a snippet from the post What Is Scaling?