To increase leisure by one hour, a person has to let go the opportunity of earning income , equal to wage per hour , which the person can earn by doing work for an hour. If more leisure is purchased, then the income effect encourages the labour to work fewer hours. Usually a typical person who works a 9-5 is working 8 hours a day and the opportunity cost for that is 8 hours of leisure. If someone's income is even higher, then opportunity cost of leisure will be increased. If somebody creates passive income for themselves, does that change their opportunity cost for leisure? Because if they are earning income without work, then their cost of leisure will not equal the income/minimum wage