I started out on Cats, but after I was finally able to buy a deed for a small workshop, I was unable to find a spot ANYWHERE to place it. (this was about 6 years ago)
I came over to Siege mainly because it had a lower population, and there was room to place a house. I was, and still am, mostly solo, so I just went about doing my thing, and collecting an impressive supply of Death Robes. As time went on, I leaned what I can do, and more importantly, what I can't do, (PvP), and became pretty settled in here.
Coming to Siege turned out to be a good thing for me because if I had stayed on a production, I would have left this game after the first year. PvM is a pleasant pastime, but has gotten completely unchallenging. I enjoy the possibility of a thinking opponent coming at me at most any given time. It adds spice to the game.
I wouldn't mind a bit higher population here either. Lately it's been getting too quiet in most places.