C of G foreward more down force required by tail.
if stabiliser fixed (Cessna 172) more up elevator to balance and so on
If tail has a moveable stabiliser
Pa18 etc forward c of g results in LE of stabilise moving down (aircraft nose up)
All flying tail PA28,C177 etc same rules nose heavy total elevator LE down to increase aircraft nose up force.
Confused? I am!!
Heavy metal always try and Keep the C of G as far aft as possible to decrease the fuel burn because of the previous answer.
less down force required by the "TAIL" so less load on wings, less lift reqired less induced drag, less fuel required for a given mach number. less dollars per air nautical mile flown.
Bottom line
MONEY!