FOG Factor (aka Friend of Gump Factor)
The FOG Factor is (at present) equivalent to the odds of the project building, based of historical attempts. For example, if a project has been around for 5 runs, but built only once (for whatever reason, dependency failure or it's own) it's odds of building are 1:5 i.e. 1/5 = 0.20. The reason for FOG factor is to identify which projects are 'stable' (in this one particular sense) and hence good dependencies to rely upon.
Each project with dependencies has a 'depth' equal to the number of unique total dependencies. Say a project A is dependent upon B and C, yet C is also dependency upon B. The dependeny depths are A:2 B:0 C:1. This is informative (along with FOG Factor, and really ought be takign into consideration in FOG Factor, but isn't yet) because it shows how many projects truly affect the project.