From On Being‘s interview with Adam Grant.

DR. GRANT: So the agreeable people are the nice, friendly, welcoming, polite — and I just assumed if you’re nice to somebody that means you care about them. But there’s this whole class of people who would actually score in the data as disagreeable givers. They might be gruff and tough on the surface. They’re skeptical, critical, and challenging. But at the end of the day, they have other people’s best interests at heart. And they’re actually, in my experience, the most undervalued people in our lives.

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MS. TIPPETT: This one is so interesting because on the surface it’s a little surprising. Then the minute you start thinking about it you think of those people who, as you say, might be gruff or stern in a way that makes you rise to the occasion, but who also have huge hearts. And you always know that. And you’re right, they’re kind of these bedrock people.

DR. GRANT: They are. And there was a software engineer at Google who had a great way of describing them. He said, “Oh, a disagreeable giver is somebody who has a really bad user interface, but a great operating system.”