What Is a "Good" Backlink?

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.

Here's what was constantly popping up in my head, maybe you can relate to some of these:

• What if I get a backlink from a profile page on a certain authoritative website (which allows dofollow links from profile pages), placed manually (not using spam software) by registering there and filling out the profile, maybe even with an opportunity to write a few paragraphs of text (if there is something like an "About me" section), basically making the backlink contextual?
• Or what if I place a backlink in a forum post (also dofollow and on a high-authority domain), but do it manually, writing a meaningful post, contributing to the discussion? This way it's 100% organic, right?
• How are those different from a guest post on the same websites (or some other websites with similar domain metrics), which may cost several hundred bucks (as opposed to 10 minutes of my time for a profile/forum backlink)?

I just couldn't wrap my head around it: if the goal is to get a backlink from a high-authority domain, why should I pay for a guest post, if I can get a backlink from the same (or similar) domain for free? Or even better: pay someone to do the job for $5-10 per backlink?

One may say that the answer was right in front of me: simple economics. If it's easy to get a backlink, then it's not valuable. And that is absolutely correct. But there were several thoughts that were clouding my judgment at that time:

• When you don't have the needed experience, the cost of just a single guest post may seem so absurd, that it's hard to shake off the feeling that you are just being scammed, that something's not right here. When you look at the number of referring domains to your competitors being in the hundreds or even thousands (just looking at the bare numbers, without knowing what exactly to look for and that the amount of actually valuable backlinks that move the needle for the competitors is much lower than the total amount of referring domains displayed in tools like Ahrefs/Semrush), it's hard to imagine how you can compete with them since you can't afford to buy that many guest posts. So the whole thing just feels off.
• Even if we assume that guest posts are indeed what actually moves the needle, it's scary to dive into it just to test it, since it's so expensive. And if it works the same (or just marginally better) as profile/forum backlinks, then it's a lot of money down the drain, so the cost of error is very high, we're talking basically a hundredfold here.
• Even if such links are weaker than guest posts, the question remains: how much weaker? And they should still pass some "link juice", right? So maybe one should start with them, and then, when rankings improve somewhat, bringing in some revenue, move on to guest posts when the budget allows?
• There are a lot of agencies that offer quality, manually placed profile/forum backlinks (they may indeed do a good job making it look organic, writing a meaningful post, etc.), and they have a lot of positive reviews. They are also pretty good at convincing you that such links actually work. Oh boy, this deserves a separate post, check it out.
• I was in doubt if Google can actually tell the difference between a profile/forum backlink and a guest post. I mean, sure, sometimes there are some obvious signs, like /forum/ in the URL, but sometimes it's not that obvious. There is a huge amount of different websites coded differently, having different URL structures, etc. Or, for example, let's say that a blog has a post with a comment section; if I place a backlink within the article itself, it's a "good" one, but if I place it in the comment section, it's a "bad" one? I mean, come on. It seems borderline impossible to tell the difference for a machine, considering the variability, right? Spoiler: wrong.

It turns out that Google is actually pretty good at detecting UGC (user-generated content) links. Tough to say how exactly they do it from a technical standpoint, but it's a fact. There is another quote from John Mueller, that I once again wasn't able to find the original source of, but it's cited often enough, for example, by the Search Engine Journal:

Even though I disagree with his take on toxic backlinks, I tend to agree with him on this one. He even says that UGC links are "easy to recognize"; well, I guess when you have as much data as Google, it may indeed be a relatively trivial task for a team of engineers.

And, of course, the referring domain must be authoritative enough, the link must not have a rel="nofollow" attribute, and all the other usual stuff that I've covered in previous posts, like "the checklist" in the competitor analysis tutorial, tips on backlink strategy improvement and how to avoid domains with spoofed metrics.

Any proof?

Oh yeah, I almost forgot. There are 2 case studies that I have conducted that support the claims in this post.

The first one is once again about my SaaS, where at first I opted for mostly UGC links, persuaded by a certain agency that they work, check it out: Surviving SEO Agencies #1: do UGC backlinks work ($9k case study)?

The second one is a deep analysis of one of my competitors, who absolutely destroyed the SERPs in less than a year with only guest posts: How to conduct a competitor backlink analysis and predict the budget (case study). I haven't mentioned in that article that they had absolutely zero UGC links, so there you go. Those guys certainly knew what they were doing, so them not bothering with UGC links is, in my opinion, another indicator that they have no value for SEO.