According to the google webmaster guidelines, paid links should include a nofollow in it because. Affiliate links help webmasters to earn money and consequently, they should be “nofollow”. In a 2012 interview, Matt Cutts from Google mentioned that Google handled the largest ad networks. However, today there are many more affiliate programs than in 2012. I think that it is useless to take the risk to leave an affiliate link without a nofollow. Since paid links are under scrutiny by Google, they may have implemented new ways of detecting affiliate links.
According to our observations, we found that the most popular affiliate links websites like thewirecutter.com or moneyexpert.co.uk always used nofollow or disallow behind a redirection. This means that the most successful websites that use affiliate links have been successful without external links and dofollow. Another example of a successful website that only