Why does it say that your stimulus check is an advance of your 2020 tax refund?

[Cicada]

10. Section 6428 of the cares act. It's free money, no need to pay it back

The CARES ACT gives us all a tax credit for our tax year beginning in 2020. Some individuals actually have a tax year different from the calendar year. Some people chose a different tax year, such as children of rich people who elected a year starting, say Feb 1, when they first filed, at age 1 say. In the time of high inflation some did this to delay tax payments 11 months. It was a mistake. Explaining that to people, like bankers, was a huge pain, the tax delay wasn’t worth it. My firm which advised this was too smart by half, as they say.

But I digress. Most humans start Jan 1 so for the tax year 2020 we all get a tax credit created out of thin air of, say, $1200. The $1200 check we get is advance payment of that credit. When 2020 tax returns are filed you will have a tax credit if $1200 against any tax you owe. But you already got it, in the stimulus check, most likely but not always, so next year it shows as zero on your tax return line named magic tax credit out of thin air, or whatever. We don’t pay back anything in 2020. But a person who somehow didn’t get the 1200 they deserve in this year will get it next year on their 2020 tax return.

There are other rules so those making more than $75,000, $150,000 married joint, don’t get the check and won’t have a credit next year.

It’s free money, you don’t have to pay it back. Weird process but it’s free money, relax.