One near universal constant in both physical and virtual games is the expansion. Especially in realm of board games it is hard to think of ones which don't have an expansion. And most of those are probably flops or too new to have an expansion out. Often these expansions completely alter mechanics in the basic game. For example the new expansion to Pandemic, the In the Lab expansion, completely reworks the mechanics for curing a disease. It changes it from simply turning in 5 matching cards to manipulating the infection cubes in a lab to sequence the disease. The new mechanics are super thematic, but also add a lot of additional complexity to the game. The expansion forces the players to do things that are unlike anything in the base game.
Pandemic is not an isolated incident. 7 Wonders: Leaders, King of Tokyo: Power Up!, and Wiz-War: Expansion Set* each introduced brand new mechanics which add complexity to the base game. In all these cases the new rules in the expansions could have easily been included in the base game. For some of these games the expansion tends to be a critical part of experienced players enjoyment to the point where they won't play without the expansion. Personally I consider the Cities & Knights expansion key to interesting play in Settlers of Catan.
The question is why weren't these expanded versions of the games simply the base game? It is not just that they were developed later in response to fan demand. I remember reading that Klaus Teuber intended ships and sea exploration to be part of the initial release of Settlers of Catan. But this feature was not added until the Seafarers expansion. So why was Seafarers not included in the base Settlers game? Are all these designers just money hungry wanting you to buy multiple $40 to $60 boxes to have the full game? Or is there a reason why releasing a simpler game could be better?
The obvious answer is of course it is about the money. But it is not as simple as simply wanting a reliable revenue stream with yearly expansion. Releasing a simple base version of a game actually increases the rate of adoption and reaches a wider audience than releasing the full game in all its complexity. Not everybody is a hard core gamer and wants to spend 30 minutes or more learning the rules and setting up the board to then play for 2-3 hours. Especially when they might find themselves in a helpless position a hour in and have to suffer through the rest. Arkham Horror, I am looking at you. This lower barrier to entry will make people more willing to try it as the rules are both more understandable and there is less risk of wanting to quite before the game is over.
Having this lower barrier of entry through releasing a simpler game increases the spread of the game through 2 mechanisms. First more people are willing to purchase the game to try, reaching a more casual audience. The last time I was in Target, they had Settlers of Catan, Pandemic, and Ticket to Ride base games. This is a huge recent development. Games like those used to only be found online or in hobby gaming stores. Now they are main stream enough for big retailers to carry. What is notable is the expansions are usually not found at big box retailers. This implies that it is the simplicity of the base games which attracts customers, not the depth found in expansions.
The other way a lower barrier to entry helps is through providing an easy way to teach non-gamer friends how to play. This might not seem like a big deal, but presenting people with something they can easily grasp in one play is huge. People then feel like they get it and want to play again. I think this is a huge reason 7 Wonders is such a favorite with my more casual gaming friends. The base game is simple and fast so it tends to click quickly and make people want to play again.
Most games I will teach without the expansions because there is no reason to add the complexity for new players. This is especially true with Settlers of Catan, which has a surprising complex base rule set. There is a lot going on to acquire resources and then build more of your colony. Compare this to the simplicity of matching cards to build routs in Ticket to Ride and it is easy to see that the addition Knight mechanics and city improvements are unnecessary complications when teaching the game.
Clearly starting with a simple base game is the optimal way to release a board game. This is not just from a money perspective but also from an enjoyment perspective. Game designers, in general, want to share their creation with as many people as possible and want to see that people are engaged and enjoying themselves. It is this passion to create things that brings people together that really makes a designer great. Note that the simple versions have a bigger penetration than the expansions because they are easier for players to digest. Which is fine. If a casual gamer just plays the basic version and doesn't have interest in the extra complexity of the expansion that is one more person enjoying time playing than if the game had been released as one big compilation. And the hardcore gamer is happy because he has the extra rules to add depth for him to analyze.
*Yes I did reference the original Wiz-War game and not the recent 8th edition by Fantasy Flight Games. The reason is 2 fold. First there are no expansions for the new version. Second the first expansion for the early editions of Wiz-War added creatures, the upcoming expansion for the 8th edition does not. I am still super excited about getting my hands on a copy of the new edition, but it didn't work as well for this example.
