What mistakes you've made launching your product on PH?

There's a ton of advice on how to get the PH launch right. But very few people share their failures. I believe failures can give us way more valuable insights than these "How to get 1k users from PH doing nothing" marketing posts. My #1 mistake that led me to a launch that got 10 upvotes and 0 comments: not having an audience to support the launch. I just asked a few friends for upvotes and that's it. I believed that my product is so good that everyone wants it. I haven't emailed my users. I haven't promoted the launch in any communities. Classic "Build it and they will come" mistake. Promotion is as important as building the product — I learned that hard way. Share your mistakes that you've made launching your product on PH.