One of the most powerful ways to understand your customers, whether they're consumer or business customers, is to discover how they "work" and write it down, delineating a day in their life.
How do the potential end users of your product spend their days? What do they do? What do they read? What products do they use? How much time do they spend using them? How would life change for these users after they have your product?
Business products are generally purchased because they solve problems, so a deep understanding of the buyer is required. If you're selling retailer point-of-sale tools, for example, can someone on your team work behind a busy counter for a few days?
There's no better way to understand than to dive in. Learn how prospective users currently solve their problems, online or off, and how they'd do it differently using the new product.
For a consumer product, the same exercise is applicable. How do consumers solve their problems today? How would they solve their problems with your product? Would they be happier? Smarter? Feel better?
What will motivate these customers to buy?
Draw a vivid and specific picture of the day in the life of the customer and do the research in the same place where they do their work or have their fun -- not in the company conference room or alone at a local Starbucks.
Check out the video below (also here) for more.