Encrypting your link and protect the link from viruses, malware, thief, etc! Made your link safe to visit.
Much like url shortener (bit.ly, adf.ly, shorte.st and others). But I think it's safer and more profitable than using a paid url shortener service. Because we have full control over the contents of an intermediate page including the type of ads being served.
You could say this is the best alternative to increase revenue from the website / blog (especially for sites that provide file downloads), without sacrificing the user's comfort from the less friendly ads. Like, pop-up ads and interstitial ads that are very annoying to users of the site.
The Safelink page can also be used automatically by placing the script code into the html template. So, all outbound links from the website automatically lead to the Safelink page before opening the actual destination page.
You can also add sites you want to filter to avoid going through the Safelink page