How does a good instructor, syllabus, and/or academic institution not need this? I went to an Ivy League school with hopefully above average teachers and saw a lot of plagiarism.
The problems are societal in nature. I don't beleive either the parent commentor or original author fully appreciate this.
Adversarial teaching environments are a symptom, not the problem. And the fundamental issues don't have a clear solution, though it is clear that the situation is far from optimal.
In principle, you remove the incentive for plagiarism by making the students' reward for their work be what they learn as a result, rather than some kind of certificate.
Oh cool, so we just need to fix a massive social problem that's generated by long-running structural trends within our society and economy. Then we can stop using plagiarism detection software.
Adversarial teaching environments are a symptom, not the problem. And the fundamental issues don't have a clear solution, though it is clear that the situation is far from optimal.