Sunan An-Nasa'i

It was narrated that 'Abdullah bin 'Amr said:""The Messenger of Allah (ﷺ) said: 'Do Wudu' properly.'"" [1] [1] Isbighu Al-Wudu'. And this narration supports the claim that some of them used this expression to mean ""three times"" for each limb, rather than ""properly