Backend developer: "The new functionality is done!" PO: Looks at tests "Seems good, ship it!"
Frontend developer: "The new functionality is done!" PO: Looks at his screen "This spacing could be a little to the right, also I think I didn't really like this text, also it should probably auto-scroll to the top and this button should change colors when I click it and also don't forget to change the error messages I was happy with before and also I think it should......"