अतिभारे नियुक्तं वा भङ्क्त्वा परमुपस्थितम् ॥ कZ_०८.५.२६च्द् ॥
atibhāre niyuktaṃ vā bhaṅktvā paramupasthitam
Or when he is assigned an excessive burden; or after breaking an understanding, he then goes over to the other side (i.e., defects).
Excess demands convert cooperation into resentment; once a compact is perceived as broken, defection to a rival becomes rational.