Sectioned forms are great for the entry of complicated information. The user benefits from having the full context of the form, instead of a multi-page form like a wizard. The user is free to fill in information throughout the form instead of linearly, affording greater flexibility.
… of the product. Wrong solutions can be fixed, but non-existant problems aren’t adjustable at all. So, how can we be sure to tackle a real problem? Alas, we can‘t be 100% sure, but we can minimize the risk a lot by observing and talking to people. Hence, uncovering the problem and building solutions customers really want.