Why did slaves have different experiences of working on plantations?

I'm not sure if this is 100% true, but its probably because slaves had less harsh daily work compared to other slaves because of their connection to the slave owner or if they were lighter skinned. I heard that light skinned slaves were better treated(but still suffered of course) but had less harsh works and were sent to clean the houses. I'm not 100% sure about this though

Explanation:

because slaves had masters whose personality was kinder or more mean than others

Explanation:

after the spaniards introduced horses to plains native americans, the lives of the tribes changed. tribes became less settled and sedentary. the horse allowed them to hunt animals such as bison or buffalo, and, instead of staying in one place, tribes began to be nomadic.