Today is the 38th anniversary of the first time I played D&D, which is also the first time that I heard of D&D. That's a long time, and as it goes on it gets harder and harder to remember those early days and what they were like.
The right post to write to ask, I suppose, is what have I learned? Hm. I can't make a good treasure table. Most attitudes about the game come from people who have played it for three to five years (the length of high school and college), people who are either ready to quit or have become so established in their game play that they cease to question. I've learned that I've been working on my world longer than any rational person ought to and that I'm still game to keep going.
I've learned a great deal about the world I would never have learned had I not been hunting along book shelves and through the internet for ideas. I've learned that I have the sort of obsessive personality that would have been better pointed at being a lawyer or a researcher, except that I was just too damn creative and resistant in my character. I've learned that its possible to make some headway as a random, obscure, disconnected designer but no more. I've learned that given time and greater access to educational materials that I ever thought possible has enabled me to solve magificent problems that were, 20 years ago, insurmountable.
I've learned to wait for the next idea. I've learned that wikis are a better world-building friend than anything else I've known. I've learned that players are plentiful, so long as the light above the DM is bright enough. I've learned that good players are annoying, stubborn, self-aggrandizing, stultified in their habits and the only people really worth running for. I've learned that I'm worse than everybody.
I've learned how young I was 38 years ago. I've learned how stupid I was. How little I understood. How deluded were my ideas. How much time I would be forced to waste before I would begin to see. How many hundreds of hours I would burn making tables and charts and lists that would, in the end, be thrown away or simply lost, from lack of worth and lack of use. I've learned that everything I made or drew or ran in the first 15 years of being a DM was destined not to survive to the present, at least not the form that it does now. I've learned that all of that period was like living in a chrysalis, in which the only valuable product that had to come out of that mess and stumbling around was me. I wasn't making a world, I was making me.
Not that it matters, because I've learned it had to be that way. All that time had to be spent. I can't express how many useless times I tried to create a treasure table without ever once coming up with a working answer. No matter. I had to learn. I had to see. I had to come around to where I am not by the longest route possible because all the short routes don't have enough scenery.
I've learned that making a game and a world has very little to do with what I've done. It is all about what I'm going to do.