There are lots of different opinions out there when it comes to link building, there are those who believe it is all about quality content or link worthy content. There is a fundamental problem with this sort of link building theory and that is, where are you going to find those that will link to your content, and is your content really that good?
On the other hand you have those people who believe link building is about processing as much content as possible and distributing it over the web as many times as possible, building hundreds of links every single week.
Both have a fundamental problem and that is they are not taking into account link acquisition rates. You see those webmasters who know their seo techniques also know that Google and other search engines prefer to see links been built gradually over time. Therefore the rate you build links matters a lot when it comes to where you rank for a given keyword.
When you start a new seo campaign you should be thinking along the lines of making everything you do look as natural as possible. If you build 30 manual links the 1st month, then aim for 50 the month after, gradually increasing each month.
You don’t want to start a campaign building 400 links and continue to do this month after month, this looks unnatural and the search engines will pick up on it. Build slow and steady and you will be rewarded with a high Google ranking.