An article that was presented by Martin Fowler in 2010, named the Richardson Maturity Model (RMM), and its principles, which were explained by Mike Amundsen in his book, RESTful Web Clients, speak of a maturity model, which can be used to identify which level an organization is on and what else they have to do to achieve the so-called Glory of REST:
By Martin Fowler, available at https://martinfowler.com/articles/richardsonMaturityModel.html
The RMM classifies APIs based on their architectural maturity. As we can see from the preceding diagram, it is possible to see that the higher the level (Level 3, for instance), the closer the API is to the REST Architectural Style (Glory of REST), and the further away it is from Level 0: The Swamp of POX.