The Prophet ﷺ noticed some of his companions hanging back, so he said, "Come forward and follow my lead, and let those behind you follow your lead. People will keep falling behind until Allah puts them behind."
أخبرنا سويد بن نصر قال أنبأنا عبد الله بن المبارك عن جعفر بن حيان عن أبي نضرة
أن النبي ﷺ رأى في أصحابه تأخرا فقال تقدموا فأتموا بي وليأتم بكم من بعدكم ولا يزال قوم يتأخرون حتى يؤخرهم الله عز وجل
Reported by Muslim, The Prayer, chapter on straightening the rows and establishing them and the merit of the first row and then the next, and so on, no. 438, from the hadith of Jafar bin Habban, with the same chain, and it is also in Al-Kubra, no. 870.