I don't follow. You can imagine that you have two offers: one job pays $80K/year and one pays $100K/year. Then by taking the first job, there is an opportunit

I don't follow. You can imagine that you have two offers: one job pays $80K/year and one pays $100K/year. Then by taking the first job, there is an opportunity cost of $20K/year, because you can only have one job at a time, and you had a "better" offer. But there could be a different latent risk in the 2 jobs. So using that model leads you to evaluate the two opportunities differently. You need another concept to explain the choice; opportunity cost alone doesn't do it.