A famous quote (often wrongly attributed to Albert Einstein) says:
“Given one hour to save the planet, I would spend 59 minutes understanding the problem and one minute resolving it.”
One might argue about the exact ratio between “understanding” and “resolving” (one minute — or 1/60th of the total time available — sounds short to me) but there is one undeniable truth in the statement: You are better off spending much more time understanding the problem than blindly jumping into solving/building mode.
Which is pretty much the opposite of how many people interpret the Lean Startup movement. A, in my eyes, common misunderstanding: Come up with a half-baked idea, launch an MVP, get some feedback and iterate. And iterate. And iterate.
Sadly what happens more often than not is that, due to the fact that companies don’t have a good grasp on the problem they aim to solve to start with, begin their journey from a place so far off that they just can’t get to product/market fit (or run out of money or willpower pivoting from one failed MVP to the next).
What I suggest you do instead is to deeply focus on understanding the problem at hand. Get into your customer’s head, spend time with her, feel her pain. Only when you feel secure in your grasp of the problem space, I suggest you start building your MVP. Chances are — it won’t be far off from what your customer desires.