Because some platforms
are better than others.
And why do we tell others this? Why?
Because people like to brag. If you didn't know, humans are mammals. Mammals have competitive instincts. Denying those is to make yourself less human.
dont deny, do it ... until you realize how silly you actually are doing it

very few mammals can realize things, we are probably only mammals with the capability of logic and strategy
after a while being in the spot light you realize , i dont need this BS, in fact i just look stupid to some and admired by the ones i really dont care to be admired from.... this is when you grow above the mammals.. and again its nothing wrong with being a mammal, i been there too
this days i only upgrade my system if i really need it, and i wont waste my time impressing others, and even if i have unlimited funds and time i would not post it around i keep it secret... any one can believe what ever he wants.. i could not care less
of course you can go the other way around and make "being the best" your hobby, in that case you better be the damn best there can be.. after all its you life goal to be the best.. but then why would you post here and not run moding competitions.. if you post you 6ghz 16 core, 256gb ram, 8 each 2gb $5000 GPU's system you just look silly
the ONLY useful thing about posting you system on such forum if its LOW and not high, so other people with similar systems know what to expect, then your helpful and not just a dush trying to brag that he can afford an I7 and whoha what a suprise it runs the game... thank you very much
