The answer lies in the last word of your question...community.
Imagine you're a stranger in town. Instead of people casting awkward, nervous glances your way, or with paranoia or even hysteria, hurriedly shooing their children back home, you have people stopping what they're doing and making time to welcome you wholeheartedly into their community.
Feeling lost? They don't just point you in the right direction; they actually walk you there.
Got a lot of questions? You're right at home. They've been there, done that. With great empathy, they don't just give you a flippant response and walk away. They take the time to teach you. Link by link, they connect with you. And they don't stop there. They show you how you can link up with others.
Your hub break down? Like omipresent roadside service, they help you fix that flat hub; add renovated spark to that rundown plug; install a video on your dashboard; provide your vehicle with SEO tune-up; and make your writing engine run faster and smoother with outstanding jet fuel capsules.
They help you find your voice, restore your self-respect, and invite you to be a significant member of the community.
Best of all, they mentor you in the greatest responsibility of all...
They encourage you to help others in return.
Because, ultimately, that's what HubPages is all about.