If you count your stitches at the end of the row, you know if you got it right. The number of stitches remaining is the number of stitches on the right (which will now become the left) needle. It's an opportunity to check for mistakes.
Cheating is an option. . . . Cheaters never win and winners never cheat, but smart knitters who want to retain an iota of sanity do, cheerfully. ~~Kory Stamper