I find the visual structure useful for seeing where something is still too broad. A large branch may contain several different customer problems. Breaking it down can help us choose a smaller opportunity and identify an experiment that would teach us something useful.
For a simple, hypothetical example, a team might want more new customers to finish a first useful task. If research shows they cannot tell which option fits their situation, several responses are possible: clearer descriptions, a guided first step, or a different starting point. The next question is which assumption we need to test before committing to one.