When Duryodhana saw the strength of the Pandavas, he went straight to his teacher, Dronacharya, to complain. Duryodhana felt weaker when he looked at the strength of the Pandavas.
If your sight is stuck on the other, you are bound to feel weak. Duryodhana failed to see his own massive army because his eyes were fixed on the other. He started getting angry, frustrated and tense, and started accusing his own men of not doing anything for him.
Strength comes from gratitude. Strength comes from recognising one’s strength.