Q: Why do music producers always stare at waveforms?
A: Because human ears actually get tired. "Ear fatigue" is a real medical thing.
After listening to a heavy kick drum for four hours straight, your brain physically stops registering the volume correctly. A waveform visualizer gives you hard, undeniable, mathematical visual proof. If the audio wave for your snare drum is physically half the size of the hi-hat, you know instantly your mix is objectively ruined, even if your tired ears can't hear it anymore.
Q: Can a waveform tell me if my song is completely ruined by clipping?
A: 100%. That's its primary vital function.
A healthy audio waveform looks like a jagged, dynamic mountain range. If your song hits digital clipping (meaning you pushed the volume way past the legal digital limit), the tops of those mountains will literally look like someone took a massive pair of scissors and violently chopped the peaks clean off. They become perfectly flat blocks. That translates directly to nasty, crackling distortion.