Testing to failure is pretty common in rocketry. If you don’t push the limits you’ll never really know where the limits are.

This has been SpaceX’s methodology for a long time now and has gotten them to the point where they have the most reliable western launch vehicles ever launching record amounts of mass to orbit each year at record low prices.

I truly hope that if you ever design a rocket yourself, that you will test it. I have no idea why you'd think testing is a terrible thing to do if it has to do with rockets.

Why precisely? Can you elaborate?