What the data actually shows
Neal Roese and colleagues' research established that regret is among the most frequently reported emotions and that it clusters in the life domains people value most — work and career, romance and family, and education. Far from being a rare or pathological state, regret over significant decisions appears to be a routine feature of a reflective human life, experienced across cultures and ages.
The engine of regret is counterfactual thinking — the mind's habit of simulating how things could have gone otherwise. Gilovich and Medvec (1995) showed that this thinking shifts over time: in the short term people more often regret actions they took, while over the long term regrets of inaction, the roads not taken, tend to loom larger and persist longer. Either way, the comparison is to an imagined alternative, not a known one.
Crucially, that imagined alternative is systematically distorted. Research on affective forecasting and the 'impact bias' (Wilson and Gilbert) finds that people consistently overestimate how intense and how long-lasting their emotional reactions to outcomes will be, and underestimate how well they adapt. The 'grass is greener' pull of the unchosen path overstates what you actually know about it, because you only ever lived the path you took.
Why this feels different from how it actually is
Regret feels uniquely heavy because the unchosen path stays perfect in your imagination while the chosen one accumulates all the ordinary friction of real life. You compare a road you actually walked, with its visible costs, to a road that was never tested and so never had the chance to disappoint you. That asymmetry quietly stacks the comparison against your real decision.
It also feels different because people underestimate their own adaptation. While deciding, and in the aftermath, the mind forecasts that a disappointing outcome will hurt as much in a year as it does now. In practice, people adjust to most outcomes far more than they predict, so the dread and the lingering 'what if' are usually larger in anticipation than the lived reality turns out to be.
And big decisions carry an identity weight that makes their regrets feel especially exposing — as though the choice reveals something about who you are. That weight is part of why regret concentrates in exactly the domains you care most about; the more a decision mattered to you, the more counterfactual thinking it tends to generate, which is a sign of how much you valued it rather than of a mistake.
What the research says to do about it
Naming regret as normal is itself useful, because treating a universal emotion as a personal failure tends to add a second layer of distress. The research is clear that regret over major decisions is common and human; recognising that can take some of the sting out of the feeling without pretending the decision was costless.
It also helps to treat the imagined alternative with appropriate scepticism. Because counterfactual thinking and the 'grass is greener' pull systematically inflate the unchosen path, reminding yourself that you do not actually know how the other road would have gone — including its own hidden costs — brings the comparison closer to reality. The alternative you regret is a simulation, not a record.
Where regret points to something genuinely changeable, the research on action versus inaction suggests that taking a reversible step now can prevent the longer-lasting regret of having never tried. And where a decision is irreversible, the consistent finding that people adapt better than they expect is reason to give yourself time before concluding the choice was a lasting mistake. For regret that is severe, persistent, or interfering with daily life, a qualified mental health professional can help.
What the research says does not help
Repeatedly running the counterfactual — replaying how much better the other path would have been — does not resolve regret and tends to entrench it. Because the imagined alternative is rosier and untested, rumination feeds a comparison that was distorted to begin with, deepening the feeling rather than settling it.
Telling yourself you should have no regrets at all is neither realistic nor helpful, since regret is a near-universal response to consequential choices. Demanding its absence usually just adds self-criticism on top of the original feeling. The more honest position is that some regret over big decisions is part of having made them.
Judging a past decision purely by how it turned out — outcome bias — also distorts the picture. A reasonable choice made with the information you had at the time can meet an unlucky result, and treating that result as proof you decided wrongly manufactures regret over a decision that was sound when you made it.
Real numbers in context
It would be misleading to attach a precise prevalence figure to 'how many people regret big decisions,' and the research does not support a clean one; what it establishes is that regret is among the most commonly reported emotions and concentrates in major life domains like career, relationships, family, and education. The honest summary is 'near-universal,' not a specific percentage.
The more quantified pattern is about timing and distortion. Short-term regret skews toward actions taken, while longer-term regret skews toward inaction and roads not tried. And affective-forecasting research consistently finds that people overestimate how intense and lasting their emotional reactions will be — the impact bias — which is why much regret fades faster than the person feeling it expects. The feeling is real and normal; its predicted severity tends to exceed its lived one.