Sometimes yes sometimes no.
When I was 5 years old with 105 fever and I didn’t want to get into a cool tub of water I remember my dad hurting me a little to keep me still while I was screaming and crying and my mom wrapped a wet towel around me. Did the end justify the means? Absolutely. No question in my mind.
Or, that girl who was in the news who was ordered by the courts to receive cancer treatment that she was refusing. I said here on Fluther when we discussed it that they should tie her down and give it to her. From what I understand, in retrospect she’s glad she was ordered to do it.
What about when a parent makes their kid do things they really don’t want to do? That happens constantly, sometimes under threat of punishment, sometimes by bribing the kid. Usually, the end is pretty important and worth it.
Then there are things that the means are illegal, lack integrity, or hurt others, and the vast majority of the time the end does not justify the means.