A low agreeableness score means you give less weight to other people’s feelings and interests when deciding what to say or do: you are more sceptical of motives, more comfortable with disagreement and more concerned with being right than with being liked. It does not mean you are unkind, and it is not what disagreeable means in conversation.
What it does not mean
It does not mean you are a bad friend, partner or colleague. The six facets of agreeableness are trust, straightforwardness, altruism, cooperation, modesty and sympathy, and a low domain score usually comes from two or three of them, not all six. A person low on trust and cooperation but high on straightforwardness is a blunt, loyal sceptic: hard to fool, honest to a fault, slow to warm. That is a recognisable and valued kind of person, and nothing in the scale says otherwise.
It is not a measure of empathy in the sense of understanding others. Low scorers often read people well; they choose to act on their own judgement rather than on others’ feelings. And it is not a verdict: the site never colours a score as good or bad, because each end of each scale has strengths and costs.
What the research finds
Agreeableness predicts relationship satisfaction and lower conflict with partners and peers, with small to moderate effects across large samples, and it predicts volunteering and helping (Ozer and Benet-Martínez, 2006). Its link to job performance is weak and depends on the job, unlike conscientiousness (Barrick and Mount, 1991); low agreeableness is associated in some studies with higher earnings in competitive roles. On average people become more agreeable through adulthood, especially after fifty, so a low score at twenty-five is likely to be a less low score at fifty-five.
What it means for your results
Look at the facets before the domain. If you are low on trust, the trust test explains that facet on its own; if you are low on modesty, that is a different thing again. If your percentile is between the 25th and the 75th you are in the band where half of everyone sits, and the word low does not apply. If it is below the 25th, the description above is what the score means, and nothing more.