the cake model of product planning
it's actually two different models for how to introduce new scope to a product over time. I strongly prefer the bottom. To explain...
Most organizations plan out new products and experiences using the model at top. They start with cake, then maybe add some filling, and then plan to add the icing as the final step. It makes sense from an operational perspective. But there's problems with this model from the customer's perspective and from a competitive perspective. Cake with no filling or icing isn't that appealing. Plus, anyone can make cake.
A better model for planning new experiences is the cupcake model. Start with something small, but very desirable. Move on to additional releases that also balance the expected (cake) with enough filling and icing to create a great experience that sets you apart.