Oh, but it's so much more convoluted than that in the US.
Employers are supposed to take all of the expected taxes out of paychecks and transfer them, and Social Security and Medicare taxes are supposed to come out. Those are actually the two most important ones for employers to get right, IIRC.
Social Security and Medicare taxes are the easier ones, but then there's federal, state, local, and school taxes, that can be difficult to calculate, so often the employer will get it wrong, and you'll either owe money or be owed money by at least one taxing body.