I didn't mean the orientation of the fan MediaMan, I meant a poor contact with the heatsink, poor coverage of thermal paste, etc.

Having already fitted the thing myself I am fully aware of how it is meant to work. Hot air rises, etc, therefore, it makes sense to either suck the air to the front (then allow it to move upwards in a natural convection current), or to help it along and blow it up towards the fan exhausts at the top of the case.