Abū Hurayrah noticed the Prophet ﷺ paused between the takbīr and the recitation, and learned he said: “Allāhumma bāʿid baynī wa bayna khaṭāyāya…” (al-Bukhārī). Samurah reported two pauses: after the opening takbīr and after the recitation. (Tirmidhī — ṣaḥīḥ) — giving those behind time to recite.
العربية: عن سمرة بن جندب رضي الله عنه قال: «حفظتُ سكتتين في الصلاة: سكتةً إذا كبّر الإمام، وسكتةً إذا فرغ من القراءة». (الترمذي).
Imams: pause briefly after the opening takbīr and after recitation — it aids khushūʿ and the followers.