Salah is a unique ibadah that Allah Ta’ala has ordained, all the other forms of ibadah came down via the medium of Jibril (‘alayhis salam). As for salah, Rasulullah (sallallahu ‘alayhi wasallam) was given this great miracle during the journey of Mi’raj. This goes to show the greatness of salah.
Repetition is the best form of emphasis.
The most repeated command in the Quran is of establishing salah,
Further more we find no other ibadah that has a caller calling out for it.
Here is a series of talks by My Beloved Father; Moulana Haroon Abasoomar saheb (may Allah protect him) on salah: