All Because of a Penguin
Some people see ghosts in their nightmares. Others see monsters, or shadows, or witches. In 2012-2013, webmasters saw penguins.
Before those years, building a strong SEO through backlinking was really simple: seed, seed, seed as if there were no tomorrow! The amount of backlinks was considered a plain indicator of website relevancy, and SEO agencias as well as webmasters who wanted to work in their sites' SEO would simply spread links across the Internet. For a while, it worked. Then, Google developed his algorythm, Penguin, and everything changed.
Huge websites, some of them of quite relevant companies, saw their rank collapse overnight. Old strategies needed to be quickly updated, and everyone had to adapt to this new scenario. What made sites rise high in their ranking suddenly became a penalizer, and all work done had to be undone for the sake of the target site. Webmasters and SEO agents needed to review every single one of the links sown in the past, and put them out or at least disavow them in order to get some of their rank back.
Enhancing page rank through link building is still one of the pillars of SEO, that hasn't changed so far. What has changed is the criteria that Google uses to determine whether or not a site should be qualified as good, and so link building strategies had to be adapted.
Link Building that Actually Works
Google Penguin has changed some things since 2012, and it has always done so with no warning and no tardiness. Good webmasters know this: any time, the algorythm could change again, and once more the work of months or even years could turn against the target sites. Some decide to play safe and only use low risk strategies, while others would take a daring step and place their bets on higher levels.
What is now clear is that link building isn't a safe and secure way into optimization as it was in the past. While the intention behind Google Penguin are undertandably good, now webmasters have to think carefully and evaluate before engaging in a link building strategy.
What is for sure is that some approaches are always harmful. They belong to the old school of SEO and are now obsolete; only the worst SEO companies would fall back on these. Mainly, paid backlinks on low ranking websites such as suspicious directories, penalized websites, and absolutely irrelevant domains. This, which once worked perfectly and was very easy to do, has now become a big no-no of SEO.
If you want to perform link building the right way, you have to know what works and what doesn't. Here[As we is a nice article on how to balance anchor texts so they look best to Google Penguin, we won't dwell on this too long. Enough to say that every detail, for as little as it could seem, will have a significant weight on your webpage's ranking. Good SEO companies have all these aspects under control and run an audit in order to check this and balance it back in case that it isn't optimized.
Back to link building strategies. The strategy of choice is simply a matter of risk-management: the ideal is to find approaches with low risk and high benefits. You can play safe by relying on quality content, for which you will never be penalized because there is no point in that. However, this is a low impact approach and you shouldn't expect a significant rise in your PR if you don't seed a few links here and there. Your oh so good quality content will go unnoticed, which is the opposite of "traffic".
Purchasing links is a riskier bet, because sites which sell backlinks can be penalized, and that penalty will make your links become toxic for your domain. However, if this doesn't happen, this strategy can work very well. A good way to decrease penalization risk is to go for guest content that is subjected to editorial review. This is harder to get, but is still safer, and works as well as paid links do, as long as the domain is wisely chosen.
Fixing the Problem
You should periodically run link audits on all your website's backlinks. If you have been penalized, running a link detox is indispensable for said penalty to be lifted. If you haven't been penalized, you should still run an audit so you detect links that could cause you trouble in the future.
As you have seen, some websites get penalized overnight, and the algorythm itself is being refined time after time. Those links that don't harm your rank right now but could become a threat in the future should be deleted, or at least be kept under watch.
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