There are conflicting opinions about the correct etiquette for following someone back on Twitter.
For instance, Mashable explains that sometimes - especially for businesses with thousands of followers - following back every single person will do nothing but clog up your Twitter feed.
"Don't fall into the trap of something I call a 'courtesy' follow - that is, following someone that has followed you out of a desire to appear grateful," Sheena Medina, community manager at Fast Company, tells the media outlet.
Conversely, Laura Fitton, inbound marketing evangelist at HubSpot, explains to the media outlet that not following someone back means you're telling them "Thanks for the support, but you’re not important enough to us to be willing to listen to you privately." This can be detrimental to your business, especially if you're just starting out and aren't a brand name.
However, Fitton and Medina do agree that automated "Thanks for following" responses are unnecessary, since they seem robotic and lack authenticity.
Designer Jay Goldman's blog notes that you should take into account whether or not your new follower has a website. It's not a "hard and fast rule," but it can help a business to get an idea of a new customer's likes, dislikes and voice.