Why Do People Re-post Subjects?

I've been following seriously a trend on this chapter on Nairaland, and it's so bad to see topics that had been debated before being re-posted.
I keep asking myself, what do people who do this want to gain? do they want to mislead the others or confuse them? a lot of people are looking for job and its really bad to take advantage of such and start spreading false and outdated information.
I really hope Seun will do something about this and stop this trend. And to you who keeps reposting outdated vacancies, I have an appeal ,  PLEASE STOP.