I used to wonder as to why I ended up with less oil drained than was claimed as oil capacity in my owner's manual, until I removed the oil pan. In which case, the baffle of whose purpose is to keep the oil level above the pump's entry pipe during when the vehicle travels around tighter curves at higher speeds, was stamped with reinforcing ribbing.
Since I do not use my vehicle for rally sport, I felt free to perform the following modifications on the baffle of which those who indeed use their vehicles for rally sport should first reconsider applying this procedure well over, before doing this themselves.
I started off drilling 4 millimeter holes in each stamped indentation of which held oil in a pool. I then chamfered the drilled holes, in order that the burrs themselves could otherwise not be able to trap oil:
:

Because the drain plug was attached vertically to the bottom of the pan instead of from the side, oil was trapped above the level of the thread boss of which was welded onto the pan. In order to reduce the amount of waste oil remaining in the engine, I ended up filing an indentation into the this thread boss, until I have reached the level as close to the bottom of the pan as possible:

The best solution would have been for the manufacturer to have manufactured the drain plug to where it could have been removed horizontally. Nevertheless, one could always weld
together his or her own custom aluminium oil pan accordingly