Ten fallacies developers believe about design and user experience:

1) Telemetry accurately and without bias represents how your product is used.

2) Security necessarily means reduced functionality.

3) The product should be optimized for the least capable, newest users only.

4) Any advanced configuration options will confuse users so much that the product will fail.

5) There are no consequences to changing the interface every one or two product cycles.

6) People passionate about your product are irrelevant to its success, and it’s ok — even desirable — to piss these people off.

7) Developers know better than users how to use the product.

8) If users find some unexpected way to use your product, they are doing it wrong.

9) All users use the same set of features the same way.

10) Design is different than how the product works.