Even nofollow links can hurt my website?

Question

I have a forum with around 20,000 organic traffic with 100+ forum threads and 1000+ answers.

Many users already have requested that allow them to use a signature.

Allowing it will be result of having thousands of links from my forum.

Sure, I can no-follow them. But I want to know that even they are no-follow, will it affect my forum to badly?

Answer 1

Marketing and general people advice you do not worry about nofollow outbound links, but matt cutts said nofollow link sculpt your pagerank (check 4th and 5th Question). I don't know weather it is still true or not, but wikipedia working fine with tons of nofollow outbound link. So It is not like it will affect badly.

If your forum have quality good content contributed mostly by your user, then allowed them to have signature. But I will probably add some limits like if user have more than 50 post then allowed signature, but if they simply post just to reach your limit, then probably I will go for manual approval.

Answer 2

I hear this a lot when talking to some of my clients that they want to link out to their friends companies and so on, while its a nice gesture it can also have some undesirable effects which I'll break down into a few sections for an easier read.

• UX (User Experience)
  • Having links to non-relative pages or sites impacts UX, especially when found within the content areas of the page, sidebars are partly-exempted from this notion.
• High authority sites link to other high authority sites...
  • It is no secret that Google and Bing favours sites and pages that stink of authority these type of sites generally don't give out links like candy and when they do its to other high authority sites.
  • Good pages can rank even better when linking out to other relevant pages, think about it for a moment, it happens a lot... you go to a website, find information you need but want more insight so you find a link which takes you to another site that either confirms, or gives you even more information, this from a UX stand point is excellent, users leaving a site shouldn't be seen as a negative because the more UX you have, the more people link and the more people whom link the better you rank which equals more visitors.
• Relevancy
  • Linking out to sites or pages that are not relevant to the page can dilute the page, just think for a moment, you have a page about 'Web Design' and then within the content you link out to a blog all about deodorant, is Google or Bing going to prefer that page if the outbound link is to another page about web design or deodorant... I'll give you a tip... its not the later.
• Disavow
  • It is believed by the SEO world that Google uses the information provided to them within the disavow submission, sites that obtain excessive amounts of submissions can expect Google to view the site with some negativity.
• Best Practice
  • Generally speaking it is best to avoid linking out unnecessary, especially since most forum signatures are displayed within the content areas of the page. To keep Google and your users happy the best practice and good UX would be to have the usernames of the forum posts link to their profile page on the forum and there they can add a BIO with a link. You could go one step forward and disable all profiles that do not include a BIO, that way you have less low quality pages appearing in the index.