That's why if your Zodiac sign insists you're an honest, loyal person, you're prone to believe it, regardless of whether your everyday life backs that up or not. ("I mean, it's been months since I cheated on my spouse!") But broad statements like that always work better if the description is vaguely positive, regardless of whether it makes logical sense. ("You're from Florida? Ah, I knew it. You have the savvy courage of a Floridian!") Even Zodiac sign descriptions that that include character flaws tend to spin them as a positive:
Scorpios, like their namesake, the scorpion, put up an outer shell and may seem prickly. But once people get beyond the shell, they find a loyal, loving person whose passion knows no bounds.
You read that and say, "Hey, that's true! Everyone says I'm an asshole, but that's surely only because they don't know the real me!"
And then there's apophenia, the brain's tendency to infer a nonexistent pattern from statistical noise. That's a result of humans being so great at pattern recognition that sometimes we can't turn it off. Caveman Gug noticed that some of the leaves in the bushes outside his cave were disturbed, but went hunting anyway and was promptly eaten by a saber-toothed tiger. Caveman Oog, Gug's cave mate, saw that, and now he never goes hunting if the leaves outside his cave were disturbed. Sure, it's probably not a saber-toothed tiger every time, but evolutionarily speaking, it's better to be superstitious than supper for a smilodon.
If you combine the need to make sense of a chaotic universe with our desperate need to understand ourselves, you have a perfect recipe for "The patterns in the sky tell me you are a generous lover."