There are basically 2 types of backlinks that do not violate Google's spam policies: "natural" backlinks and "outreach" backlinks. "Natural" backlinks are those that are created without any action on the part of the website owner, which happens very rarely (if you are not a well-known brand) and may be considered to be no more than a pleasant bonus; you obviously can't consider those as a core part of your off-page SEO strategy. "Outreach" backlinks are those that are created when you reach out to website owners and ask them to link to you, without offering anything in return (to be specific, "money, goods or services", as Google puts it). There are a lot of guides out there that will tell you how to do link outreach, and it can be a viable strategy to some extent, but there are a ton of caveats that they either don't mention or don't emphasize enough. Let's take a deeper look.

Another thesis that some SEO agencies love to throw around is that "content is king". What they mean by this is that you should simply write "good quality content" (or even better: pay for their services to write it for you since they know for sure what "good quality content" is) and that alone is enough to make your website rank higher on Google. This automatically implies that backlink building is not necessary or important. This is a very dangerous delusion, which is very widespread as I see from discussions on r/SEO, comments on YouTube, etc. In this article, I will approach this topic from various POVs, and show proof of my claims.

There are a number of SEO agencies that offer "quality" UGC backlinks as a service. "Quality" in this context means that the backlinks are made to look organic, i.e. they are placed, for example, in a forum post, which actually contributes to the topic of the thread, the post itself is not spammy, it may contain meaningful, unique text, the backlink itself does not look out of place, does not have a rel="nofollow" attribute, etc. This is sometimes also called "crowd backlinks" or "crowd marketing". The websites picked for these backlinks are usually high-DA ones, sometimes really high, like DR 80-90, and some of them may also have a lot of traffic, like 10M+. That's why they claim that these backlinks are powerful enough to help you rank higher in Google.

I remember when I was trying to figure out an SEO strategy for my SaaS, I had some knowledge about SEO at that point, but I was still a bit confused about what exactly I should do regarding backlinks. I knew that those were important, but I didn't know what kind of backlinks I should get. I had some understanding that there are some obviously "bad" backlinks, like those acquired by spamming forum profiles/threads, blog comments, etc. with automation software, and I also knew that a "good" backlink should be placed in a relevant context, i.e. within a relevant article on a page and that the referring domain should be authoritative enough, i.e. have good metrics, etc. But that was about it, and there were still a lot of questions that I had.

When building a prospect list for backlinking, we have to make sure that a backlink from a certain website will contribute to our domain authority, and not be a waste of time and money, or worse - harm it. Usually, we rely on domain metrics to make this decision, and it's good for a quick check, but we should look deeper into the website we're considering to get a full picture since the popular metrics can be spoofed.