A thing about Hogwarts Houses in general: they can be thought of as indications of a person’s motivation, or of their loyalties.
Gryffindors are driven by their morals and are loyal to the world, or at least to their idea of what the world should be. Gryffindors will always stick up for what they believe in, and they will help anyone in need (hence, “daring, nerve, and chivalry) unless it’s a person they feel is wrong or against them. At that point, you become the enemy.
Hufflepuffs are driven by a sense of fairness, which is not quite the same as morality. Hufflepuffs are the type to believe that everyone should have an equal chance, and they are better at seeing the shades of grey between a Gryffindor’s absolute right and wrong. They are loyal to their friends, or to the group they consider themselves a part of.
Ravenclaws are driven by enlightenment. This is very different from book smarts. It’s not terribly unusual for Ravenclaws to not excel in academics, because it’s not about the grade for them; it’s about the knowledge they gain, and whether they consider that knowledge interesting enough to bother with. They are loyal to their passions, which could be anything from books to art to fantastic creatures that may or may not be real.
Slytherins are driven by recognition. That could mean fame or power, or it could just be the validation of the people around them. They are loyal to themselves. This, by extension, means they are fiercely loyal to those closest to them, the ones they consider their own, because harm to their own is essentially the same as harm to themselves.