Market research firm Labs42 surveyed 500 Twitter users about how they interact with brands. The majority of respondents (aged 18+) followed 10 brands or less. The main reason to follow a brand on Twitter was to get discounts.
Based on these answers, it would be easy to conclude that discounts and promotions would be the quickest way to build a large following on Twitter. However, when looking at some Swedish brands, the really successful ones are using Twitter mainly as a channel to inform about products and business related topics, in combination with answering questions from consumers. Check out @hm and@spotify as good examples. Sports retail chain Stadium is one example of an account with mainly promotions, but it is only followed by 500 people.
This survey had very few options to the question “why do you follow [brands]”. Another similar survey from last year revealed that information about new products is one of the main reasons to follow brands.
Also see this white paper about Swedish businesses on Twitter: