First, the first pump of the throttle accomplishes two necessary things - 1) the accelerator pump gives an initial "shot" of raw fuel down the carb throat into the manifold plenum, which starts vaporizing to be sucked into the cylinders to support combustion, and 2) releases the choke linkage to "set" based on the ambient temperature. In cold weather that "set" will be almost totally closed, while on a nice 25C day it may only be 1/2 to 2/3 closed if it's controlled by a bimetal coil. Any pumps following only throw more raw fuel into the manifold.

In my experience each car had it's own "happy spot" for best starting, often based on the age. One was one pump to the floor & release for crank, another was two pumps, then feather the throttle a bit during crank, and one (worn out accelerator pump) was three or four good shots, then pump the fuel again during crank. Putting a "kit" in the carb generally brought them back to the one pump, release and crank. Also, it was different summer to winter, and cold start to hot start, because the fuel vaporizes at much different rates with temperature. You find the "happy spot" and live with it, and also use those facts to assess the need for a carb rebuild.

You can start new threads as you wish, and it's handy if you want to focus on a specific question and go back later to review comments. It's your call.