Dalai Lama said “Optimism leads to success; pessimism leads to defeat.” Why?

Assuming he is right; how could that be?

Are whingers doomed to failure and the enthusiastic destined to succeed?

Or is there more to it than that?

looking forward to exploring this phenomenon.

Available online - https://us02web.zoom.us/j/89568268699?pwd=M05lOWZ3RkRZbVpGVTYxT3JIQTFiUT09