Keypad:Keyboard vs. Phone

Why are the numbers on the top and bottom line of my keyboard keypad reversed from the one on my phone (i.e 7,8,9; 4,5,6; 1,2,3 vs 1,2,3; 4,5,6; 7,8,9? Is this just one of those things that is what it is?

I’ll let the Mighty SDSAB field that question: