The HSL color model is more intutive for humans than RGB (which was developed as a technical solution)
The pickers are designed so there’s no need to really know anything about color theory
Each color parameter has it’s own independent scale, so a user will understand easily what to adjust to get a desired result
What’s more, the scales change according to current color, allowing the user each time to visually understand which scale does what (e.g. I want it lighter, darker, more red, more gray…)
