Mahabharata 3.28.20

भीमसेनं हि कर्माणि स्वयं कुर्वाणमच्युतसुखार्हं दुःखितं दृष्ट्वा कस्मान्मन्युर्न वर्धते

bhīmasenaṃ hi karmāṇi svayaṃ kurvāṇamacyutasukhārhaṃ duḥkhitaṃ dṛṣṭvā kasmānmanyurna vardhate

Our plain-language meaning of this verse is waiting for scholar review.