Minimum RAM advertised in computer programs is usually the ABSOLUTE MINUMUM that will enable the program to run without inflicting mental damage to the users or making them smash the computer.

When reading "enable the program to run" do not assume that the words "effectively" or "satisfactorily" follow or are meant to exist in the context of the sentence.

As a company, you want to broaden your user base as much as you can. So saying that program XXX runs on 2.2 GHz and above, with 512 MB RAM and above will deny you potential customers. Lowering the threshold will earn more customers, and sometimes "oblige" them to upgrade, because our lives are software-driven.

Ever tried to run Windows 95 on a 386DX 40MHz with 16/32 MB RAM (circa early 90's) after installing it using floppy disks????
I have done it. I was never the same after that.....