PR Why do retailers leave tweets unanswered? A recent study of 50 large brands found that fewer than one-third of those that have Twitter accounts answer customer tweets. They interact more on Instagram or Pinterest. By Matt WilsonJan. 7, 2013 SHARE To read the full story, log in. Become a Ragan Insider member to read this article and all other archived content. Sign up today Already a member? Log in here. Learn more about Ragan Insider.