I've been having some issues subdividing a simple mesh. Normally I expect on subdividing a face the new intersecting lines are made with new polygons, but this isn't always the case. On one face the subdivide command will work but then selecting another face it doesn't work. However, if I select the edge select tool I can see that actually the loop around the face I tried to subdivide is indeed subdivided.
To produce this mesh I simply started with a cube and extruded a surface a few times. The smaller cubes on the far right are extrusions made after subdividing a surface successfully. What am I missing?

