Loss aversion — the tendency to be more motivated to avoid a loss than to achieve an equivalent gain — shows up even in domains where every outcome is a gain of some kind, purely based on how the outcome is mentally categorized. A missed putt that costs a stroke relative to par (a bogey) is experienced as a loss; a made putt that gains a stroke relative to par (a birdie) is experienced as a gain — even though, from a tournament-scoring standpoint, one stroke is one stroke regardless of which side of par it falls on.
The fact that this shows up in elite professional performance, where every player has overwhelming incentive to make every putt, is what makes the finding so clean: this isn't a matter of insufficient motivation or skill, it's a demonstrated asymmetry in the underlying psychology of gains versus losses that persists even under maximum pressure and expertise.
Economists Devin Pope and Maurice Schweitzer analyzed over 2.5 million professional golf putts, including many by Tiger Woods during his most dominant years, comparing putts of equal difficulty attempted either to avoid a bogey (avoiding a loss relative to par) or to score a birdie (achieving a gain relative to par). Across the entire dataset, players were measurably more accurate on the bogey-avoiding putts than on the equally difficult birdie putts — meaning even the best golfers in the world, putting for their livelihood in nationally televised tournaments, unconsciously bore down harder to avoid a loss than to secure an equivalent gain.