When students cheat they end up in the habit of cheating and taking short-cuts, and in the long run this makes their lives worse.

Cheating is like speeding.

If students cheat at subjects that require competent professionals skills, such as medicine and engineering, then we will end up with professionals who cannot execute their professional duties correctly, and that will be bad for society.

I have a strong intuitive feeling that cheating is wrong.

If everyone cheated, it would undermine the very purpose of the activity being performed, so that the activity itself would fail.