Benefits of Link Building include:

They help bring awareness to your website (particularly if you are part of a reciprocal link building situation). The audience of the website you quote or mention will surely see your article on social media or through search.

Because your site is getting more visibility, writers will be more apt to see your site and link back to it (giving them that contextual, external link).

The company you mention may want to reach out to you or simply just include that article on their website, which earns you a backlink (great for SEO link juice).

Because you have more recognition, you’re likely to see an increase in social media shares. You not have your audience and the audience of the website you mentioned sharing the article, not to mention it is a higher quality article.

They give you more credibility because you’re willing to link out to authoritative sources, which prove you have done your research and look to others to help create the best article you can create.

Not only are you credible, but you’re also trustworthy. Some sites try to know it all, but contextual links help prove that you are a site that cares more about trust than being the answer to everything.

Google likes to see sites improving reader experience, so your PageRank and rankings should improve.

Your site should gain more traffic because it gains more recognition.

If your site is gaining more traffic, you’re likely to see an increase in sales.

Last but not least, you are offering more information to your reader. This should always be your number one goal.