Not long ago did having low-quality backlinks was also considered to rank pages by Google. But since the Penguin algorithm update, this game has changed everything. A lot of top-notch bloggers lost the traffic and rank drastically before they could know what has happened.
It took quite a long time to understand the reason the drop. But once understood they did not commit the mistake ever again. Not only having backlinks is important, but having quality backlinks is what matters. If you see backlinks from spam or automated websites, remove it immediately.