A mindset develop through a realization based on the past of your own life. Missed opportunities and loss of motivation that occur within one's life time leads one to believe that if they had, hadn't done certain things in their life's e.g They maybe could've been something that they aren't today. This isn't to say that for this person They can no longer achieve it but that they should work towards their dreams for better or worst. People with this mindset take every opputunity and don't take the life that they are living for granted.
Friend 1
"Man, i wish i could've been famous.. maybe if had just stuck to the acting when i loved it instead of playing video games i could've been"

Friend 2
"Seems like your starting to develop like a could've been mindset?"
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