The Argentine setup

German charcoal barbecues function like this. You fill’em up, coal burns down (gets very hot at some point). When you need another round of coal you lawyer another batch of coal on top. 

The result is very bad. You have quite a variable temperature of the course of the batch of coal. Once its kicked off it's a bit of a runaway situation.

Widely used as such in Alemania

Separating what should be separated

You separate the making of the burning coal from using it. The benefit are obvious and plenty.

Temperature control - by pushing more or less burning coal under the barbecue area. You can ramp this up as you like, for guests coming later. For slow cooking followed by more heat to sear it.

Plus, the “charcol production area” is really designed for burning stuff, i.e. more air. See on the left of the picture. That’s why that also works better.