No, it broadens and deepens understanding.
Alternatives come from that understanding. Criticism is the fundamental step towards alternatives.
No, it broadens and deepens understanding
How exactly do you come to that conclusion?
Edit: “Thing bad” doesn’t broaden or deepen anything. “Thing has specific shortcomings which aren’t present in specific alternative to thing” is a useful criticism. Criticism without alternatives is just called complaining.
Not always, sometimes it’s just an acknowledgement of insurmountable facts. Pointing out the inability of a particular engine to overcome the laws of thermodynamics to output more energy than is input is not useful criticism. Pointing out the mortality of individuals is not useful criticism. Those shortcomings are specific, but unless there’s some alternative that doesn’t have those shortcomings, those aren’t useful observations, they’re pointless complaints.