What Hogwarts Houses Are Really About
I think that a common mistake when it comes to think about the houses and sorting in general, is that people think too much of it simply as a means of categorizing and labeling people. However, first and foremost, within the Potterverse, it is a system of placing students into a community which will influence their growth in the best way for their needs.
When the students enter Howarts, they are 11 years old. At such a young age, most children don’t really have a concrete sense of self. All they have is potential. An 11-year-old going into Slytherin may not have the best work-ethic, or know how to manipulate their surroundings. They have the seeds of ambition within them, and with the fertilizer that is the Slytherin house, can be grown into a “true Slytherin.” Slytherins in the Potterverse have such strong manifestations of Slytherin values and traits, not because they came naturally, but because they spent 7 years of their lives being nurtured and brought up in the Slytherin environment. They live in a community where ambition and cunning are highly valued and emulate it themselves until they are molded into Slytherins.
A strong example (and one of my fav character arcs ever) is Neville Longbottom. He is clearly not the perfect ideal of a Gryffindor during his first year. But he goes from nervously and shakily warning his friends against breaking the rules in his first year (plenty of character development happened there already too), to killing a giant snake and standing up to Lord Voldemort himself and facing certain death. It wasn’t that being in Gryffindor made Neville into a hero, it boosted the potential to be a hero that he had in him all along.
So, for some “real-world connections,” this explains why, for those of us who like to self-sort as a part of enjoying the Harry Potter experience, it’s not always so clear what house we belong to. Many of us are young adults, and haven’t been raised in a purely “Ravenclaw” environment. We grew up in the real world, where many traits from all of the houses are valued in different measures in different cultures and even families. We’re all a complex mix.
I will never be as much of a Ravenclaw as Luna Lovegood is. No one is purely any house (at least, until one of you rich nerds decides to make a school based on Hogwarts and raises kids in the same way). However, we can still emulate the house traits and values. The moment you say “I really want to become the kind of person who would be sorted into Hufflepuff,” you can identify as a Hufflepuff! So, in the end, it’s just like the Sorting Hat said. What house you are is your choice. It doesn’t define you, it just guides you.