It’s called [Loss Aversion](https://en.wikipedia.org/wiki/Loss_aversion), and is a cornerstone of behavioral economics.
Losing something you already have impacts your life more than getting another of that thing.
Lose your house, you’re homeless. Huge impact on your life. Someone gives you a house, it’s a big impact, but having an extra house is nowhere near the same level of change as being homeless.
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