Common advice is to build a product that solves problems you personally have. Reading through https://www.reddit.com/r/startups/comments/bjwn5p/how_to_build_a_successful_product_by_justintv/ solidifies this advice and encourages you to also talk to customers that potentially share your problem.
What if I don't really have any problems? My biggest problem is finding a product idea. What words of wisdom do you have for me?