It's true---everything you have ever done is wrong. If you are a developer, look at the code you wrote five years ago---it's wrong. If you collect and store data---it's wrong.
This is the nature of human endeavor. The world used to be flat. The earth used to be the center of the universe.
Discovery and development is an iterative process. What we do today will likely be replaced tomorrow. Just because we can't be perfect at the outset doesn't mean we shouldn't try.
Just because our data doesn't represent the "truth" doesn't mean we shouldn't use it. We take our best shot at it and refine it as we better understand the problem. Otherwise we sit in an empty room holding a blank slate...