The cost ? Well lets take this into the extreme. Lets assume you adopt a new opinion that a life is only worth it's economical value. The amount of mental work

The cost ? Well lets take this into the extreme. Lets assume you adopt a new opinion that a life is only worth it's economical value. The amount of mental work to integrate that believe in your current set of opinions (by changing them) is huge. So you'd rather not do it. Another example: the lie your company is on a good path. Knowing accepting it is on a bad path, means a lot of work. And as we know humans are lazy by design.