"Did we build it right?" vs. "did we build the right thing?"
Engineers use these two words almost interchangeably in casual conversation, and in systems engineering that's a costly habit. Verification and validation are two separate checks that compare a finished product against two completely different reference points. Mixing them up doesn't just cause semantic confusion — it's how entire products get built, tested, signed off as fully compliant, and shipped, only to fail at the one job they were actually supposed to do.