Much of the evil in this world is caused by good intentions and beliefs that sound really nice.  When good intentions and nice sounding beliefs are divorced from truth and logic, they can cause more harm than that caused by those trying to cause harm.

I like this quote by C.S. Lewis
"Of all tyrannies, a tyranny sincerely exercised for the good of its
victims may be the most oppressive. It would be better to live under
robber barons than under omnipotent moral busybodies. The robber
baron's cruelty may sometimes sleep, his cupidity may at some point
be satiated; but those who torment us for our own good will torment
us without end for they do so with the approval of their own
conscience."