Accepting a Guest Blog Post may be tempting, potentially saving you a day or two doing research for a new article of your own, but in my opinion, it also tends to degrade the quality of your site.
I have encountered many blogs over the years with little originality, writing mainly short how-to's and tips on technical things. The SEO cummunity is notorious for this, possibly because competition is very high in this area.
SEO is a very small part of owning a website, and ideally you really should not have to think about it at all when your site is developed properly. The narrowness of the field means that a lot of people is ready to offer their advice on how you can get your web pages to rank well. This is bad, because, as I mentioned, you really should not have to think much about it.
I think articles should have a clear goal. You should never write an article just to get traffic from search engines – it will just degrade the quality of your site. If you have good content, traffic tends to come entirely on its own.
Besides, when it comes to guestblogging, why would you accept an article on a subject that you could have covered better on your own?
I do not accept guest posts on Beamtic in exchange of dofollow links, and this is unlikely to change.
Another problem with guestblogging is the overwhelming number of no-name authors who tend to contact you for blogging opportunities.
You would probably mostly want to have experts write for you.
Even if you manage to connect with an expert, what would they stand to gain from writing an article for your blog? They might as well just write for their own website for long-term gain.
This is where blackhat linkbuilding comes into the picture. Guestblogging has been heavily abused to create links.
In my opinion, there is much more to be gained writing articles for your own website, than there is giving away your content in exchange of links.
It can also be a bit illogical from a business perspective, because if you target quality high-traffic blogs, then it makes no sense for them to pay you (be it money or links) for your content. Rather, you would be paying them to have your article posted on their site, since you stand to benefit from the exposure to a high amount of traffic on their site.
Advertising on other blogs
Even without the linkbuilding aspect, you can still use guestblogging as a form of advertising to create indirect engagement with your own site. Both in form of traffic and links.
Using guestblogging for the sole purpose of building links is degrading the quality of blogging in general. Why? Because these posts tend to be of very low quality, lacking depth and trustworthiness. Plus, they might give the author an unfair boost to his own website.
For me personally, I think placing nofollow on links in guest posts makes sense, since the author will still be benefiting from the exposure, increased awareness and recognition – possibly even some traffic from the nofollowed link.
If an article is of high enough quality, and expected to bring in traffic, you might even consider to feature it free of charge (still using nofollow on author links of course).