When it comes to SEO, one of the most straightforward and simple aspects to understand is building your link profile. It makes a lot of sense that the more links you have pointing to your site, the more easily Google will be able to find and index your pages, and likewise it's only logical that building lots of links will help visitors to find your site too and make your pages look more popular and reliable.
Then the penguin and panda changes came along and made sure that all the links we built were high quality as well as high in quantity. It was no longer enough to just have lots of inbound links - we also needed to make sure they were on high quality blogs and websites.
But if you've spent the last year tirelessly getting your site onto as many high profile blogs as possible by writing guest posts and generally doing everything you can to get your links in the right places - you may actually have done yourself a disservice. Let's look at why...
Natural Link Profiles
The whole reason that Google stamped down on people spamming the web with lots of low quality and low relevancy links is that it was an easy way for people to manipulate their links profile and thus play the system. The result was that the person who got to the top of the SERPs was the person with the most time on their hands. What Google really wants to find are the sites that have lots of links pointing at them because people wanted to share them. If you get covered by the news or someone mentions you on a forum then that should boost your site - not having a hundreds of low quality links on article directories.
The problem with doing the same thing now with high quality links is that you will once again be playing the system in a way and this will be obvious to Google if you aren't careful. Think about it - if your links only ever appear in high ranking blogs then does that look natural? Does that look like people are sharing your site freely?
Worse is if the anchor text for your sites is always the exact same. In other words, if every page that links to you uses your brand name or 'click here' then it's not going to look very natural at all. Most of the links we share are simple URLs, and if we include them in a blog post they'll probably have a completely random anchor text that works in the context of our content.
Likewise you shouldn't hunt down and remove all the links to your site on irrelevant pages because that's natural to an extent too. You don't think Facebook gets links from rubbish sites as well as good ones? Or Mashable?
In other words if you really want to benefit from your efforts in building links you need to think most importantly about how it's going to look to Google. Is it a natural and varied links profile or does it have your grubby fingerprints all over it?