AppFrame Micro (AFM) is a micro-framework for PHP that has a couple advantages. AFM uses a tree-based router (similar to the one used in AppFrame Lite) for faster searching with complex URLs. Compared to many frameworks, AFM provides roughly the bare minimum although this may change depending on how much I want to expand this project.
Honestly, there is no reason. Most frameworks boast a different style and level of maintainability for developers. This is just another framework that embodies my interpretation of a simple prototyping application framework.