Name: Luis von Ahn
Advice: I don’t know if it's bad universally, or if it was just bad for me. When you’re building a product, typical advice is listen to what your users are saying. I have found that is terrible advice for Duolingo. The spirit of the advice is good, but a lot of times, there is a problem that arises. If the feedback channels are such that that only a few users get to talk to you, you are only hearing the loudest ones, not all of them, and that is where it breaks down.
We have a forum on our website where people can talk about language, but they often ask about features. I have found that listening to people in the forums is a terrible idea. For example, we redesigned the website a few years ago,and people in the forum were saying how terrible it was. Hundreds of posts about how this was the worst decision we had ever made. All the while we were looking at the metrics for the new website, and they were significantly better.
If you are just listening to the people who reach out to you, than that is a biased sample of people who are a loud minority. Of course that is not always the case, but unless you know what you are doing, you should watch out for that bias.
Read more about von Ahn: Why This Founder Says the Worst Advice He Ever Got Was to Listen to His Users