If you go out and buy links just to get your site ranking higher, here are the possible results:

Best Case Scenario : The links are on clever sites that have found a loophole in the Google algorithm and it actually boosts your site’s rankings in Google search results for a while. Every time a loophole is found, Google then modifies it’s algorithm to close it. Any boost you get will be lost in a few months, or even a few weeks.

Most Likely Scenario : Even if the links you pay for are actually created (often the link farms are happy to just take your money and do nothing) you will get no benefit at all from them, as Google recognizes them as paid links. The listings had zero impact on their rankings, but it cost them a pretty penny.

Worse Case Scenario : By paying for your links you manage to hit that magical point in Google’s algorithm where Google punishes you for the paid links, and your ranking in Google search results plummets, or you get blacklisted entirely.

So, be very cautious, when get trapped in such link building services.