अभृतव्याधितयोरभृतं तदात्वकृतवेतनं युध्येत न व्याधितमकर्मण्यम् ॥ कZ_०८.५.०३ ॥
abhṛtavyādhitayor abhṛtaṃ tadātvakṛtavetanaṃ yudhyeta na vyādhitam akarmaṇyam
Between unpaid and sick forces, he should fight the unpaid—especially those paid only at the moment (ad hoc wages); he should not fight the sick, who are unfit for action.
Unpaid troops may be demotivated and brittle, but still organized; sick troops can create unpredictable contagion/attrition dynamics and may be non-engageable in decisive battle—leading to wasted effort or stalemate.