Successive Approximation Model (SAM) is an agile development model created by Michael Allen, a recognized pioneer and leader in the design of interactive multimedia learning tools and applications.
Another key aspect of SAM that reflects a more business solution focus than ADDIE is the Preparation Phase with its SAVVY START. It is putting explicit focus on ensuring there is alignment between the actual performance needs of the client and the learning solution that is provided. Putting the AGILE workflow aside, the focus on client need is how both SAM and FKA’s Instructional Systems Design (ISD) methodologies are like each other and different from ADDIE.
SAM looks good and so does FKA’s ISD with its AGILE cloak(https://www.fka.com/agile-instructional-design/). However, looks aren’t everything. I think the take way from this is when you remove the clothes what you are left with, and what you need, is a systematic approach to cost effect designing learning solutions aligned with your client’s needs.