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." (DE)
English reference (DE): Vol. 1, Book 1, Hadith 142 (DE)
Arabic reference (DE): Book 1, Hadith 143 (DE)