Have you ever kept pushing toward a goal, even when switching to something else might have been smarter or easier?
You’re not alone—and scientists are starting to understand why.
A new study by researchers at Caltech, published in PLOS Computational Biology, explores how people decide which goals to stick with and which to abandon, especially when the environment keeps changing.
The research, led by graduate student Sneha Aenugu and Professor John O’Doherty, used a creative online game to explore this question.
The game asked players to collect different types of cards—cat, hat, and car—by completing sets in specific suits.
In each round of the game, or “block,” the odds of receiving a particular type of card changed. Sometimes one type of card showed up more often, making it a better strategic choice. However, these changes weren’t always made clear to the players.
The study found that most people kept trying to finish the card suit they had already started—even when it made more sense to switch to collecting a different suit with better odds.
This tendency, known as “over-persistence,” meant players were often more focused on finishing what they had already started than on changing strategies to get more points.
Why do people do this? Aenugu and O’Doherty suggest it has to do with something like “momentum.” In physics, momentum is the product of how much mass something has and how fast it’s going. In the case of goal pursuit, it refers to how far someone has come toward a goal and how quickly they’ve been making progress.
If someone feels like they’re close to finishing something, they tend to keep going, even if the environment has shifted and a new path would now be better.
To test how human persistence compared with optimal decision-making, the researchers also created computer algorithms that played the game. These computer players didn’t have the same emotional attachment to finishing a goal and could easily switch strategies based on changing odds.
Unsurprisingly, the algorithms performed better than the human players. But interestingly, a model based on momentum—factoring in current progress and how fast a goal was being completed—came close to matching the optimal strategy and required less mental effort.
Aenugu points out that while sticking with a goal can sometimes backfire, it’s not necessarily a bad thing. In real life, we don’t always have perfect information, and sometimes it makes sense to rely on simpler rules like momentum. It’s also possible to change our behavior if we’re made aware of how the environment is shifting—just like players in the study who were told about the changing odds and adapted accordingly.
The researchers believe that understanding how people choose and stick with goals could also help in mental health care. Since conditions like depression, anxiety, OCD, and ADHD often involve difficulties in setting or switching goals, insights from this study may one day inform more personalized treatments.
In short, persistence is powerful—but knowing when to switch can be just as important.
