
What makes a post 'bad'?
As mentioned before, certain content remains relevant only for a limited
period of time. For example, a job listing is irrelevant once that
position has been filled. Similarly, online shopping stores have to deal
with products going out of stock all the time. Some eCommerce sites
might even stop selling products from a certain vendor.
Blog posts tend to get outdated too. News highlights are a common
example. But more important are the reviews, tutorials, and round-ups
that you write. For example, the top 10 most useful WordPress plugins
might not be the same in 2014 as they were in 2013. And suppose you
wrote a plugin development tutorial based on WordPress 3.8. What if
WordPress completely changes in version 4?
Another common problem among bloggers is, they have to put up with a lot
of low-quality posts they put up initially to get their blog started.
They didn't know better then, and with the passage of time, even though
they learned a few SEO skills, they learn to ignore the old, low-quality content.
The problem
The problem with obsolete content is, it harms user-experience. If you
were lucky enough to land a visitor on your website organically (i.e.
via a search engine), the last thing you would want is to drive that
visitor away with outdated, irrelevant or low quality content. Having
bad content increases your bounce rate.
Bad quality content also continues to harm your domain authority and, if
it comes to the worst, might cause Google to slap a domain-level
penalty. This means that no matter how many good quality posts you might
have on your site, your site's SERP performance will be determined by
the bad quality posts, which become a bottleneck. So what should you do
with such content?
The solution
404 Error Pages
The most obvious solution would be to take down the bad quality post,
leaving behind a 404 error page. You can use 404s in a creative way, and
keep the visitors engaged within your website. Check out this simple,
but effective 404 page from Coca-Cola.

It is, however, not advisable to use 404 error pages. Why? Because they
alert search engines that an error exists within your site. It is not a
good SEO practice. Besides, 404 pages mostly put users off, no matter
how creative you are with crafting a custom 404 page. People tend to
bounce off the second they see a '404'.
301 Redirects
For the vast majority of scenarios, I'd suggest 301 redirecting your
expired content to another page. This is usually the best option for SEO
and can also be customized to enhance the user experience via
dynamically-generated messages. For instance, if a certain blog post had
garnered external links, you're able to retain most of the link equity
from those links via a 301 redirect (whereas with a 404, that link
equity is lost). Why would you want to lose the link equity that you had
worked so hard to obtain? Furthermore, it demonstrates to search
engines that your site is well-maintained and up-to-date or "fresh". It
also tells them where to find the updated version of your content.
Therefore it is almost always advisable to use 301 redirects instead of
404s, provided that you have, indeed, updated or improved upon your
obsolete content. If you haven't, maybe now's the time to do it, because
you're losing precious user-experience points every time a visitor
lands on your site!
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