Crimea

I wrote that (I don't remember the reason - I'm too lazy to look it up). They only captured Sevastopol, Russia's main naval base on the Black Sea. But if Russia had been too weak, they wouldn't have stopped there.

They forced Russia to make peace with Turkey, and the peace was quite unfavorable to Russia considering its victories, so their goal was 100% achieved. Perhaps, if Russia had been weaker, the terms of the peace would have been even worse, but the capture of Crimea by the English and French was not planned, and that's what I'm getting at.