Not the words you want to hear from the users of your product! It happens when you build more than you need to, when you don’t stick to simple, and improve incrementally based on real world feedback. Don’t rely on your initial design about what you should build. Designs are created in a vacuum, they are a best guess on how to build the thing you are going to build. What they really do, is document the original idea for something.
Don’t get me wrong, designs are very important, but the problem is it is very difficult to determine exactly what it is that will make your product useful, until it has actually shipped. Who’s to say all that time you spent on that feature will pay off before you ship? It may be completely ignored because people don’t like it, or just don’t have a need for it.
So next time you’re creating something, keep to the absolute essence, the very core of the product idea and deliver just that. After you ship, you’ll have no shortage of ideas about what you need to put in next. In fact, you’ll need to vet them just to shorten the list!