In a broader sense, the fact that it was already established. I was comfortable. I had all my subs. More importantly, I could search up something of interest and find people who shared that interest. Now? Now I've flown the coop and damn, it's a little scary not having everything in one tidy little birdhouse. I have no doubt I will come to love Hubski, but I can't deny that it is mildly terrifying that there is no Super Smash Bros tag yet (you guys are out there, right? Right?). I believe it's just an initial fear though. I've never been a part of the building process.
Holy shit dude, you play Smash? I was just wondering if there were any Smashers on here. Which games do you play? I'm a PM guy myself, but I also dabble in Melee and play some Sm4sh on the side when my brother is annoying enough to convince me. But, awesome! We should make a Smash tag or something.
I like to think of different web communities like these as different 'countries' with different cultures. Once you get over the initial phase of tailoring the websites to your liking, learning the etiquette, and just getting to know the place you become much more 'at home'. Sure, it's intimidating, but it would be to visit Poland as well. However, you don't get the niche communities that Reddit has on here. :/ It's just the way that Reddit was set up with the subs really facilitated a lot of small groups coming together.
I love polandball! I think reddit is still the best place for it though. With the way things are, Reddit is not good for a bunch of things it was at some point, but I think a site with reddit's design and reddit's massive userbase is still the best for polandball.