Why does the name of the w-2 affect the amount of my return?

[michalchris]

I noticed that one of the W-2s was assigned to my wife's name and when I changed it to mine, my fed tax move from a refund to liability - but the dollar amounts are unchanged.  If we're married filing jointly, why does the name make a difference when it is the total income that is calculated?

[SteamTrain]

  If sufficient $$ were in boxes 3 & 4 on multiple W-2 forms...a W-2 assigned to the wrong person can result in an improper SS refund that goes away when the W-2 is properly assigned.

Thought of, & threw out several other ideas.......maybe someone else has some other detail that would give a  similar result.

[SteamTrain]

IF you were set up to get more stimulus on that tax return, maybe moving things around changed it, and you have to run thru all of the interview sections to reset the first or second stimulus amounts.

Maybe something to due with healthcare insurance?  Run thru those questions again too.