I got into DF when it was still a 2D game and the maps were all very similar. "Deeper" meant digging more to the right. It was a lot of fun for me while I didn't know what to do or what to expect. Eventually I got to the point with the 3D version where I could embark into a horrific frozen wasteland with no supplies and still survive, and then I didn't really want to play it any more because it wasn't challenging any more.
Still a great game with some great stories though.