What I believe is it is because of the SEO friendly posting feature of steemit. Whatever is posted is shown on search engines most of the time. I got to know about steemit with the help of my brother.

But he was searching for something on google one day and was redirected to steemit while clicking on one of the result. After that the whole culture of posting and reward-based platform attracted him so much that he not only registered, but also brought me to this platform.

Thanks to Steemit Members and the creators.
Cheers!!