There is a ton of evidence that people find a loss from whatever their reference point is more painful than they find pleasure in a gain of the same magnitude.
Here is one example.
Devin Pope and Maurice Schweitzer studied the statistics of 2.5 million putts by professional golfers. After controlling for distance, they found that the pros putt more accurately when putting for par than when putting for a birdie.
Because the pain associated with getting a bogey (one stroke worse than the reference point of par) is more painful than the joy they get from a birdie (one stroke better than par), and as a result they try harder to make par putts than birdie putts.
- Thinking Fast and Slow (2011 book) by Daniel Kahneman, page 303-04
- "Is Tiger Woods Loss Averse? Persistent Bias in the Face of Experience, Competition, and High Stakes" (2009 draft) by Devin G. Pope & Maurice E. Schweitzer