A philosophical subtlety that became obvious only when framed this way in black and white:
"everything comes with an inherent sacrifice - whatever makes us feel good will also make us inevitably feel us bad. What we gain is also what we lose. What creates our positive experiences will define our negative experiences".
Examples provided: buying that house that you have to pour money to repair and maintain, marrying that person you love and struggling to continue that love for 20 years.