Why do you play as your main?

So I have been wondering, what makes people play as the character that they main? For example, I like to play as Willow because I like the feeling of having a 2000 health bodyguard following me around, and it's fun to be able to drop Ashley and have her take care of any monsters. So what do you find fun or why do you play as the character(s) you play. (Im only really talking about actual characters, no modded characters, also please don't just say "cause it's part of the meta")

I main Wilson, because I love Wilson as a person, not as a gameplay character. Is a lot of it my headcanon? ...Yeah, but none of it contradicts the actual canon, so it could be canon if Klei chose to confirm it. The moment I knew I loved Wilson was when I was making my way through the Cyclum comic puzzle, and I saw the part where (spoilers for the comic if you haven't read it yet): This made me realize that, while Wilson may be a scientist and a gentleman, he's brave and values himse