Earlier quoted context omitted.
> Don't use analytics at all but focus on your product. Huh? Analytics is how you focus on your product. By instrumenting your product with analytics, you can find out if customers are using your new useful feature or if they can't find it. If they're performing a task quickly because it's easy, or slowly because they're struggling with the UX. And you find out that customers on a certain mobile device are suffering…
> Huh? Analytics is how you focus on your product. For the first decade of my career, I really believed this, and spent a lot of time doing split tests, and studying analytics, and trying to "make things better" by understanding the numbers as they were given to me. This was a mistake. I've since learned that these numbers will rarely help me make meaningful improvements to my product, and my business. Sure, they can…
Asking what users want is not the right way to do interviews. I advise you read "Just enough research" by Erika Hall. The goal of interviews is to gather enough data points to understand the user needs and struggle, and to know their journey through the product with accuracy, and also understanding why they use or don't use a function. It is not a way to get a "wish list".
Then, designers usually have tons of tools and methods to process this data, take decisions and try creative solutions (usually more than one), and play them back to the users through prototypes to see which ones work better. You can check design thinking as a starter, but there are many more.