"Nail" is defined, according to Urban Dictionary, as "to complete a task successfully or get something right". Since it's a slang word, most translation dictionaries such as Word Reference, Larousse, or Reverso don't list this specific sense of the word.
What caption would you use in French for this meme (or any of these, for that matter)1?
And more importantly, how could I say this in French:
As good as they may be, there's an aspect Londoners cannot quite nail.
Aussi doués qu'ils peuvent être, il y a un aspect ___
1: Nailed it! memes are well-known in the social media accompanying images where someone tries to do something but messes it up massively instead, or tries to imitate something someone else did but their efforts turn out terribly (as in the image above). Of course it can be used for when someone literally nails it, such as this meme, but the sarcastic use is far more common. I'm interested in both the sarcastic and the literal sense of the word.