Exactly - certain means are perhaps inherently not justifiable. Consequentialism vs. other competing philosophical stances.

https://en.wikipedia.org/wiki/Consequentialism

I see. So the interesting moral claim is not "the end justify the means" (which is too obvious) but rather "For every mean there exists at least one end that can justify it", which is controversial.

Maybe you shouldn't use means that need justifying in the first place?

But then why do anything at all?