Due to the proliferation of tools using Big Data, marketers are often fooled into believing that they possess great insight on customers. However, this data can only scratch the surface and must not be confused with genuine market knowledge. According to a study conducted by Gartner, only one percent of companies which possess legacy data are truly utilizing it to the fullest potential. Brands need to pose certain key questions to customers to understand them better. A makeup retailer ought to understand purchase patterns and items without which certain sets of customers cannot live without. A dog food company on the other hand must know what are the special days celebrated or the pet is allergic to any particular food item.  Majority of customers do not want to be asked questions directly but feel that few companies are collecting information to help them out. Customers need to be made to understand why certain data is being gleaned from them and what are the future purposes of such survey exercises.

Source: http://marketingland.com/best-marketers-know-customers-186153