Having served as a poll worker in California, I've seen first-hand that there are real trade-offs in making things easy for voters vs. making the election resolve quickly.
In California, you can vote in any polling place in your county. You just have to fill out a provisional ballot if you're not in your assigned precinct, and you're limited to voting for statewide races and ballot measures. But this paperwork can slow down the line, and each provisional ballot needs to be reviewed for eligibility before being counted. Those are real costs on the back end for making voting convenient on the front end.
In California, you can vote in any polling place in your county. You just have to fill out a provisional ballot if you're not in your assigned precinct, and you're limited to voting for statewide races and ballot measures. But this paperwork can slow down the line, and each provisional ballot needs to be reviewed for eligibility before being counted. Those are real costs on the back end for making voting convenient on the front end.