There is a scientific article published in a peer review Sociology magazine, which idealistically stated that role-playing games are exercises in communal story creating. That’s nice, but it is of no use to anyone trying to become a better DM or to start a new D&D group from scratch.
Based on my experience, D&D is a group activity that people can engage in, if they have time on their hands. That’s obvious, but what I am saying here, is that you have a group of friends first, and then they can choose to play D&D, or some other fantasy role-playing game, or they might as well choose to play ping-pong, Scrabble, or Poker. Almost every D&D group with excellent game play involved pre-existing groups of friends with deep social ties outside the gaming hobby.
There is a common notion, that if you are a gamer, you can join a D&D group and play. That is true, for years, most hobby shops provided bulletin boards for players and games to seek each other out. There were good games and mostly there were mediocre ones. Even back then, there were DMs trying to make money off gaming, and they didn’t run good games. One of the effects of hobby shop advertising were public games, where a meeting room at a library or school was secured, and a dozen or so people showed up to play. Those games were agonizingly slow. In one I had to wait twenty minutes to say what my character was doing on the particular turn – moving forward down a dark tunnel in a conga line of the other player characters, my sword ready to strike and looking intently side to side. Sometimes smaller groups broke off from a larger one to play at someone’s house. When I started playing again 15 or so years later, again, I ran into a public game, it was just as slow, except this time it occurred to me that this was an investigative committee work in reverse. During a committee, the incident is combed over minute by minute, until it is understood what happened. In a D&D game with a large number of players, minutes are spent to work out what happens in the imaginary world in a few seconds of tactical time.
Another thing affecting the quality of the D&D game is that each player brings in his or her motivation to the table. One would assume, that players are there to play D&D and get into the story portrayed by the DM. That is not the case. That is not the case to an extent, that when players actually get into the DM’s story, start paying attention and work together, it is called players’ Agency. Too often there are games with little or no active players participation or initiative. There is also DMs incompetence, which limits player initiative.
If you are trying to start your own D&D game from scratch, it is precisely the reason mentioned above, that you need to be mindful of the team building and group dynamics. You would be naïve to assume a DM’s contract with the players – DM’s runs the story and players will participate in it. All kinds of political behaviors and pressures will come to bear to derail your story and rip your group apart. For that reason, once you recruited a bunch of strangers to play D&D, you must transform them into an informal group of friends, if you want to keep them showing up regularly and playing for months and years to come. With notable exceptions, D&D tends to be a sheltered suburban male phenomenon with the traditional conservatism of the middle class suburbanites. Shock them out of their comfy little world, and they will be loath to play in your game. Social differences will rip your group apart, if you entertain them. I had a situation where my yuppie players tried to network and leave my working class blue collar players outside. Be wary of the consumerist attitude of the players, who claim to be coming to play in your game, but not to visit you or hang out with you personally. Watch out for that person, who will insist on bringing his or her own food with them to the game. If they aren’t willing to bring food for everyone to share, and if they aren’t willing to break bread with you, then they won’t make friends with you. Their behavior is egotistical, and you need to be aware of it. If you are a grown up, you have spent a lot of time and effort to put your game together, you want to run your adventure and what you don’t need is one or more egoists in your midst, the ones, for whom the game will be an exercise in dominance for themselves and unnecessary stress for you. Watch out for signs of passive aggression. If they can’t hang out with you and others, and if they have other social agenda besides participating in your game, get rid of them.