Why do webmasters need do-follow?

We may ask something to them on why they need sites that are do-follow? What's the big difference if the site is do-follow or not? The reason why they want their sites do-follow is two thing, to increase backlinks and for SEO purposes. But what about the term called no-follow? Webmasters set their blogs, forums and social bookmarks as no-follow because they don't like spammers through their site just to increase their chances of generating backlinks.

It is important that their sites are set to do-follow, because visitors or commenters will say something unique and good quality with their backlink attached on their anchor text. Anchor text really affects your website's search results, and you must try to be specific. You just remove "no-follow" tags on your HTML of blog or website to make it do-follow.