June 4, 2019 9:43 PM
Box 17 is the amount of money withheld by your employer to be applied to your Arizona tax return. In fact, during the year, your employer sent that money to the state taxing authority.
At the end of the year, you do your federal and Arizona tax returns, and you detemine what tax you are assessed for Arizona.
If the amount of withholding (and estimated tax payments, if any) are greater than the tax assessed, then you receive a refund of the difference.
If the amount of withholding (and estimated tax payments, if any) are less than the tax assessed, then you owe the difference to the state.
Withholding is a way for the IRS and the state to ensure that you "pay-as-you-go" and are not stuck with a large tax bill at the end of the year that you can't pay.