question #1 Sahih al-Bukhari 811, Book 10, Hadith 206 : What is the significance of following the actions of the Prophet during prayer?

(He was not a liar) We used to pray behind the Prophet (ﷺ) and when he said, “Sami`a l-lahu liman
hamidah”, none of us would bend his back (to go for prostration) till the Prophet (ﷺ) had placed his,
forehead on the ground.