Most drivers will occasionally forget to apply the handbrake, but fortunately it tends to be on a flat road and the consequences are minimal. Just don’t forget to do it on a steep, snowy hill in Russia like this fellow.
Luckily the guy appears to have kept his footing as he chased the fugitive saloon and doesn’t seem to have injured himself. Unfortunately the car exits shot left so it is unclear what happened to it, though it is fair to assume the driver learned a cold hard lesson.