@Pandya I believe it to be a misguided feature, one that does more harm than good.
As such I've upvoted feature requests in the past to disable it or alter its behavior to reduce the negative side effects.
Its intention is to drive more cross traffic, and while some of that (such as @Em) turns into actual useful site users, most of it tends to distort the site's content, especially with dubious votes.
(For that matter, apparently my most recent answer suffered this effect and got much more highly upvoted than it should have been.)