I use to ask this same question some times ago. I actually discover that even in free land nothing is free ( you know what that means). All you have to day is start using pay ads it will bring the traffic u need especially Facebook pay ads it work wonders.
Paid ads aren't the only way though. I find many think paid ads are the end all-be all, but at the end of the day if you don't have a good site with good content, paid ads aren't going to do anything.