User Research is Overrated

aka "Poorly done user research is worse than no user research at all".

If you're not asking users the right questions, and havn't considered what you options for change as a result of their answers - then yeah, you're probably wasting your time (but you're just as likely to be wasting the time you prematurely jump into design and development as well...)

There's a lot of good advice in this book: https://abookapart.com/products/just-enough-research