परभूमिव्यूहे चाश्वांश्चारयेयुः ॥ कZ_१०.३.४९ ॥
parabhūmivyūhe cāśvāṃś cārayeyuḥ
And when arrayed on enemy ground, they should keep the horses moving (i.e., conduct mounted circulation/patrolling).
Mobility reduces vulnerability to surprise and improves intelligence collection, screening, and rapid response when operating without local control.