Cleaning up user generated nofollow broken links in content.

[mysitesrock]

We have a question/answer section on our website, so it's user generated content. We've programmed all user generated links to be nofollow. Over time... we now have many broken links and some are even structurally invalid. Ex. 'http:///.'. I'm wanting to go in and clean up the links to improve user experience, but how do I justify it from an SEO standpoint and is it worth it?

[MattAntonino]

I would definitely argue in favor of this. Cleaning up broken links, changing the copyright date on websites, adding new content - it all sends signals to Google that the site is maintained regularly and has active management. A site that is regularly updated is more valuable than one that is created and then left to rot.

While Matt Cutts said in 2013 (eons ago in SEO) that broken links weren't a ranking factor, the Google Search Quality Raters Handbook says they are a factor for manual review.

They actually say:

Webmasters need to make sure their websites function well for users as web browsers change. How can you tell that a website is being maintained and cared for? Poke around: Links should work, images should load, content should be added and updated over time, etc. Exercise caution relying on dates: Some webpages automatically display the current date. Rather than just looking for a recent date, search for evidence that effort is being made to keep the website up to date and running smoothly.

When the Raters Handbook says that, I fix broken links.

[BradsDeals]

Applying Broken Windows Theory to SEO is such an underrated tactic. It's totally worth the time. Will you be able to directly attribute revenue to the cleanup? Probably not. Will it improve the overall quality and user experience of the site? Absolutely, 100%, and that's where it becomes an SEO play - because that better quality and better UX exactly what Google is aiming to reward in the long run. And because your site no longer looks like an easy mark for spammers, it should attract less spam in the long run.

Also, adding to MattAntonino's comment, Paul Haahr said a few weeks ago that the quality rater guidelines are basically Google's ideal algorithm, so you can count on Google working to incorporate as much of that as they can into the algorthm over time as they figure out how to automate it instead of relying on human maintenance. So even if it's not there now, count on it being there in the future. Future-proofing is always a good idea.