I will begin with a slow introduction to the amplituhedron, carefully explaining how to extract N=4 SYM amplitudes from it in detail. Then I will point out a couple of subtleties with the procedure in the literature, in particular showing that the lop amplituhedron is not a positive geometry as previously defined. We will thus extend the definition of positive geometries and further propose a more general mathematical space "weighted positive geometry". We will also discuss implications for the "deepest cut" of the amplitude.