Why do we ignore red flags and make excuses for people we like?

Ever wondered why seemingly kind, charming people can later be exposed for manipulative or harmful behaviour? Psychology has an answer. From mental shortcuts to first impressions, here’s why we often miss the warning signs — and what to look for instead.

When someone is exposed for abusive, manipulative or exploitative behaviour, the public reaction is often the same. “But they seemed so nice.”

It’s a response we hear after workplace scandals, coercive relationships and high-profile criminal cases alike. So why do intelligent, thoughtful people sometimes overlook behaviour that, in hindsight, appears obvious?

According to psychologist Dr Emma Kavanagh, the answer isn’t that we’re naïve or bad judges of character. It’s that our brains are designed to make quick sense of the people around us. Those mental shortcuts help us build trust and navigate relationships — but they can also make it surprisingly difficult to recognise red flags, especially when someone has already convinced us they’re kind, trustworthy or caring.

Creating a shortcut to disaster

It raises an uncomfortable question: how can so many people have completely different experiences of the same person? According to Kavanagh, author of The Psychopath Effect: The mind-altering power of the psychopaths among us (Seven Dials, £22), the answer lies in the way our brains naturally make sense of other people.

“We build a schema of who somebody is,” she explains.

A schema is a mental framework — a shortcut that helps us organise information and navigate the world efficiently. Rather than judging every interaction from scratch, our brains build a picture of who someone is based on what we’ve experienced so far.

As Kavanagh puts it, if we didn’t create these mental models, “we would have to start again with every person we meet.” When someone consistently comes across as warm, thoughtful and reliable, that picture quickly takes shape.

This is someone I can trust.

This is a kind person.

Most of the time, these mental shortcuts serve us well. They help us build relationships, cooperate with others and feel safe in our social world. The problem comes when someone’s behaviour no longer fits the picture we’ve created.

When the person doesn’t fit the story

Imagine discovering that someone you know well has behaved cruelly towards another person. Perhaps they humiliate a colleague. Perhaps they’re dismissive towards someone they see as less important. Perhaps several people begin describing experiences that don’t match the person you’ve always known. Suddenly, your brain has two competing stories.

Kavanagh describes this as schema-incongruent information — new evidence that clashes with the mental model you’ve already formed.

“If somebody is nice to me, I form the impression that they are a nice person,” she says. “But then when they do something that doesn’t fit, my brain has a problem.”

That problem isn’t that we can’t recognise bad behaviour. It’s that our brains instinctively try to make the conflicting information make sense.

Do we change our opinion of the person? Or do we explain the behaviour away?

“It doesn’t fit with the person that I think they are,” Kavanagh says. “So my brain tries to make sense of that.”

Maybe they were having a bad day. Maybe there was another explanation. Maybe we’ve misunderstood.

Sometimes those explanations are entirely reasonable. People are complex, and one incident rarely tells us everything about someone’s character.

But when we repeatedly use those explanations to dismiss the same pattern of behaviour, we may be protecting our original impression rather than responding to what’s actually happening.

Why changing our minds is so difficult

Reassessing someone isn’t simply about updating an opinion. It can mean rethinking our own experiences and memories.

If someone we trusted behaves in ways that contradict everything we believed about them, uncomfortable questions often follow.

Did I miss something? Was I wrong about them? Should I have seen this sooner?

“We’re changing our understanding of our own reality,” Kavanagh explains.

That’s one reason people can struggle to accept evidence that challenges a long-held view of someone. The story we’ve built about that person has become part of the story we’ve built about ourselves.

Patterns matter more than first impressions

Kavanagh isn’t suggesting we become suspicious of everyone around us. Everyone makes mistakes. Everyone has moments they regret. The important distinction is between a single lapse in judgement and a consistent pattern of behaviour.

Healthy relationships aren’t built on perfection. They’re built on accountability. People make mistakes, acknowledge them, learn from them and change.

The warning sign isn’t that someone has flaws. It’s when the same harmful behaviours continue, while the explanations never stop.

As Kavanagh puts it, “The person you know is the person they consistently are.” First impressions tell us how someone wants to be seen. Patterns tell us who they are.

Words: Lucy Rawlinson, Images: Shutterstock