There are three reasons.
- More links
- More traffic
- More credibility
More links are always a good thing.
Think of links as the road traffic moves through on the web. If there are no roads to where your business “lives” online, namely its website, it’s far less likely that the visitors you want will end up getting to you.
That’s true whether you’re talking about search engines or links from other sites. Search engines use a mysterious cross between the number and quality of links to your site in their determination of whether you should be number one or number 701 for your desired keyword.
In addition, the “nicer” the road, the more traffic will flow through it - think of an authority site linking to your site as a highway that leads directly to your site, and one from a reciprocal link or link exchange scheme as a back street in a sketchy neighborhood full of potholes.
More traffic, also good.
From social bookmarking, this traffic is often targeted. Through tagging, the description someone writes, or the title they assigned to your link, the person who discovers the submitted link on a social bookmarking site knows exactly where they’re going, and why they’re interested in getting there.
It’s like seeing the cover of a magazine on a rack. That’s what pulls them in, they see a headline - to get to the story they are compelled to take another action.
The more credibility thing is a bit harder to explain, so we’ll go with another analogy.
Let’s say I made a movie and I thought it was fantastic. If I’ve never met you before, and I tell you, “hey, I made a kick-ass movie, come see it!” - you may come see it, you may not.
It depends more on how much time you have and if you’re interested in that kind of movie, even how nice of a person you are, than my opinion.
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