There are some very successful design researchers who routinely ask customers to write love notes or break up notes to their brands. This creative and fun approach can (often unwittingly) get powerful insight into the perceptions of customers.
Design thinking is an iterative process that helps you move from having a seed of an idea to a plan for experimenting on a small scale. Using design thinking, which is based in the scientific method, helps you question your assumptions and explore a wide range of possible solutions to the problem you are trying to solve.
Jeffrey Sanchez-Burks, professor of management at the Ross School of Business at the University of Michigan, talks about the importance of challenging your question to ensure you are solving the right problem.