If you have a registration system on your e-commerce website, then it take too much time of user to checkout so user get bored of it and thus it will decrease your sale. But, If you use WooCommerce Social Login, then it save user’s time so it will increase your sale.
When a customer first visits your site, you can simplify checkout by allowing them to check out as a guest. However, this introduces friction for customers that want to purchase from your store more than once (and hopefully many of them do!). They’ll have to create yet another username and password. WooCommerce Social Login makes this process as easy and secure as possible – customers can log into your site using their Facebook, Twitter, Google, Yahoo, LinkedIn, Foursquare, Windows Live, VKontakte (VK.com), PayPal, Instagram and Amazon accounts instead of creating a new user account credentials.