Why creating a detailed customer definition is paramount to your startup success?
Whichever stage your startup is, you are always searching. Searching for customers is the most painful search of all, as very few companies can survive without customers for long. You can "spray and pray," but the chances you'll spend time, energy, and money, not hitting anything.
To win, you must aim well, and aim well; you first need to decide - what you are aiming at.