That's bad advice. I mean it really depends on the elo you are in, if you are in low elo ya run but if your in higher elo and know the people you are playing with aren't retards and will turn on that guy and help you kill him then do it.
The biggest thing I noticed in low elo is people who are gonna die anyways don't turn around and do damage and get the enemy low so your team mates can clean up- Most the time people who have no chance of getting away keep running and do no damage to someone and it's pointless because if you know your dead anyways u might as well at least lower their health for your team.