Why did the rainbow become a motivational speaker?

This joke gets its chuckle from some clever wordplay, specifically with the phrase "bright outlook." A rainbow quite literally presents a bright, colorful spectacle after a storm, creating a beautiful visual. But "bright outlook" also perfectly describes the optimistic and hopeful perspective that a motivational speaker aims to instill in their audience. The humor comes from applying a human characteristic to a natural phenomenon, twisting a visual trait into a personality trait.

Rainbows are a natural wonder, formed when sunlight shines through water droplets in the atmosphere, typically after rain. They've long been symbols of hope, promise, and new beginnings in many cultures and mythologies, often appearing as a sign of beauty and calm after turbulent weather. This long-standing association with positivity and emerging from difficulty makes the rainbow an ideal, if whimsical, candidate for a job that involves inspiring others to look on the bright side.