Whenever I hear a British accent in America, the conversation practically starts itself. “Oh, you’re British, right?” A few laughs later, numbers get swapped.
That’s harmless at a party. But in a leadership role, the same pull shapes who gets hired, who gets the stretch assignment, and who gets the higher performance rating. In CARE to Win, this is named as one of two biases that undermine Relationships: the similar-to-me bias.
What is Affinity Bias?
Affinity bias, also called similar-to-me bias, is our tendency to favor people who look, act, and think as we do. In CARE to Win, I break it down into three lines:
The bias: “We are naturally drawn to people who look, act, and think like us.”
The effect on Relationships: “We act favorably toward some people and unfavorably toward others, based on their similarity to us.”
The cure: “Stop surrounding yourself with people like you. Start challenging yourself to engage with all types of people from all walks of life.”
This isn’t a character flaw. It’s simple wiring. Research on attraction, including a 2008 meta-analysis by Montoya, Horton, and Kirchner, shows similarity pulls us together far more reliably than “opposites attract.” The brain’s reticular activating system filters what we notice, and it is designed to look for sameness. Buy a new car, and suddenly you see that model everywhere. Meet someone who shares your background or work habits, and you feel instant comfort.
The problem is what that comfort does to our judgment when we’re making decisions about other people.
How Affinity Bias Shows Up in Leadership: An Alexample
I am a worker bee. I am drawn to other worker bees.
Early in my career, I worked seven days a week and gravitated to the people on my team who did the same. I sent weekend, late-night, and early-morning emails. When people replied, I felt rewarded, so I sent more. Those who matched my pace got more of my time and attention. Those who didn’t, my brain filed as lazy and not passionate about the cause.
It showed up in hiring, too. I would ask candidates questions like, “Are you a strict forty-hour-week person?” If their answers differed from my own: NEXT! I wanted to hire clones of myself. Mini-me’s. I can’t think of anything worse!
The bias compounded. I am an “activator” who likes to push the start button and figure things out on the fly. Surrounded by fellow activators, the team often launched projects without a clear path or outcome in mind. The result was a culture of “ready, shoot, aim.”
After DX lost some of its employees, I realized my values weren’t necessarily shared by everyone on the team, and that they shouldn’t have to be. DX rebuilt its culture around working smart over working hard and began hiring people who think differently on purpose.
The question I still ask is one every leadership team should ask: How many good people did I fail to hire due to the similar-to-me bias? How many good people did I lose because of this?
Where Affinity Bias Costs the Business
Performance reviews. Organizational behavior research summarized by Jerald Greenberg notes that when managers formally evaluate direct reports, “the more similar the parties are, the higher rating the superior tends to give.” It runs the other way, too: employees trust managers who seem like them, which earns them better ratings, which deepens the bond. The bias becomes self-perpetuating.
Hiring. Most leaders know outright discrimination is wrong. Affinity bias in hiring is quieter and more subtle: rating a candidate from a familiar university over one from a school you know less about, or favoring the local candidate whose experience you recognize over one who trained abroad. Each call feels reasonable. Together, they ultimately narrow your talent pool.
Social bubble blindness. A team can look diverse and still think alike. You don’t achieve deep diversity simply by making your team look like an ethnically diverse college brochure. What matters is whether your people approach problems from genuinely different angles.
Culture Add vs. Culture Fit
My recommendation: Think in terms of culture add versus culture fit. Hiring for fit reinforces the culture you already have, blind spots included. Hiring for add brings in perspectives that shake up stale thinking.
Teams built from one profile create redundancy and diminishing returns. Teams built on complementary strengths become more than the sum of their parts. I have a low preference for Clarity, so I deliberately surround myself with people who have a high preference for it and can help shape strategy.
To break out of the sameness bubble:
Bring people who are unlike you into interviewing, hiring, and promotion decisions.
Assess your team’s working styles and pair people in complementary ways.
Regularly ask your team whether your decisions feel fair. Bias is a blind spot by nature, and this only works where people feel psychologically safe.
Let’s Work it: Candidate A or Candidate B?
You’re down to two finalists. Candidate A is different from you in age, gender, and background, yet you click immediately. They seem coachable, though their experience doesn’t exactly match the role. Candidate B is similar to you on paper, but the interview has no spark. B also has excellent references and the skill set your team needs.
Who do you hire? Honestly, it depends. A could thrive on an established team with plenty of Clarity and Autonomy. B may be the better choice for a new team that needs someone to build structure. The point is to notice which pull you’re feeling, and why.
Relationships: The “Who” of the CARE Equation
This chapter closes the Relationships section of CARE to Win, which sums up the CARE Equation so far: Clarity is the what. Autonomy is the how. Relationships are the who.
Biases like this one tempt you to bond only with those who reflect your preferences and worldview. If you’re not careful, you’ll end up with a team that looks and thinks like you—and that’s a recipe for blind spots, not brilliance.
On a psychologically safe team, people collaborate freely and ask thoughtful questions. Without safety, you get silence, gossip, and “heads down, hearts out.” And as technology reshapes work, this is the human edge: AI can do a lot, but it can’t CARE. It can’t connect. It can’t build trust. You can.
Start, Stop, Continue
Before your next hiring decision or review cycle, ask yourself:
Start: What am I not doing that I need to start doing to change the similar-to-me bias in myself and my team?
Stop: What am I currently doing that I need to stop doing?
Continue: What am I currently doing that I should continue doing?
Next month, we will turn our focus to Equity, the final piece of the CARE Equation, and the principle of treating people how they want to be treated.
Explore These Ideas Further
The concepts of the similar-to-me bias are explored in more depth in Chapter 11 of CARE to Win: The 4 Leadership Habits to Build High-Performing Teams. You can learn more about the book and download a free preview here.
