Spam filters of the major ISPs* use a plurality of factors to determine the ‘spam score’ and reputation of a sender, but one factor weighs more than all others: recipient engagement. 

If recipients interact with the emails they receive positively (open them, click on links, don’t mark as spam, etc.) then it’s regarded as the strongest indicator that it cannot be spam. This cannot be faked by senders. 

At follow.it, followers explicitly stated that they want to receive the content for websites they decided to follow. Also, many users receive news in their «Newspaper», an email containing news from various sources they are following. The probability that followers interact with those emails in a positive way, i.e. open & click on them, is very, very high. 

Compare this to the standard email newsletter providers: they send marketing emails on behalf of companies to users who didn’t ask for those, just because the company got hold of their email address… (sounds familiar? ;)

That’s why follow.it’s sender reputation is excellent, which ensures that your emails land in people’s inboxes and have maximum chances to get read & clicked on.