Same here, I received a message from Hive.Buzz yesterday about completion of one year on Hive. Like you said you didn't know what were you up to when you joined this site, I was the same.
I joined and forgot all about this site after doing a couple of posts in the free write and cloud community. But then I started posting regularly from June this year after I heard people talking about this site.

You have done a lot in these four years and motivate people like us. I am inspired by this post and willing to do a similar one but maybe next year :) I have nothing much to show yet.