Is this not automatic in most of the countries of the world?
Not even in developed countries! If you go to the US for example you will find people doing everyday transactions such as wage payments, taxis or grocery shopping still using pieces of paper with numbers on them. You have to see it to believe it.
This is true: I know a business that employs about fifteen employees, and one of the owners looks at the withholding tables every two weeks.
I would guess it is not automatic in most countries of the world, except for a few developed countries.