In SEO, the concept of focus keywords is entirely made up!
Anyone using WordPress knows Yoast SEO’s plugin, which helped popularize the idea.
In whatever CMS you have, a primary keyword may be defined for a page in order to provide recommendations on where to include it.
It’s not anything like PPC where you bid on keywords though!
The closest we ever had to them is meta keywords, which Google discontinued using a decade ago.
Google uses countless signals, like relatedness, to determine what your page is about. However, across on-page SEO factors, your title should best summarize the main keyword you target.
The whole notion is both useful and not. Having your content team aware of that keyword theme is vital, yet it should be…
- inextricably tied with the page’s copy (not just what you want to rank for).
- as specific as possible.
- addressed naturally & compellingly.
This is all important especially since user engagement is a big part of the algorithm.
As a result, some pages will not have much of a keyword focus, especially an ‘About Us’ page for example. That’s fine. When in doubt, create for humans and not search engines!
Secondary keywords, while also invented, can ensure you include subtopics that align the page with search intent. If you have enough to say on a subtopic though, create a new page!
SEO is not an exact science. It’s a combination of best practices directly from Google (which should NOT be followed blindly) along with industry specialists contributing their opinions. Even within SEO you’ll find different styles, all supportable.
Use focus keywords as guides and never an “end-all-be-all” for your content… don’t forget they are imaginary!