First, let me clarify what I mean by "Plus Alpha" game design. Let's say there's a game that just came out, called "Shootman" where you run around and shoot enemies with a gun, controlling your character from a first person perspective and running through mazes. This game is popular because before it game out, no other game had done this. The publisher was successful with this game, and fans of the game want more, so the publisher releases a new game, which they design like this: "What new features can we add to Shootman to create a new experience?" This is the formation/codification/CoD-ification of genre lines in action, and similar effects can be observed in music, literature, and board games. Anyway, the developer ends up making a game that's like "Shootman" except with jumping and platforming, or like "Shootman" with a focus on puzzles, or like "Shootman" with a elemental-weakness-based combat system... and the game is okay.
This style of game design has plagued recent AAA titles in video-gaming because from a business perspective it makes a lot of sense. It's low-risk, high reward. Part of what drew me into board games to begin with was the innovation in design; there wasn't really such a thing as 'genre' beyond the theme of the game (or lack thereof). Sure, common mechanisms existed, but those mechanisms were things like "tile-laying" (putting a thing next to another thing) "bidding" (any number of different twists on bidding) "area majority" (most things in a place wins) but those common mechanisms are very, very vague. Agricola and Dominion are the "Doom" or "Wolfenstein" of Board Gaming, (Yes, I'm aware that Agricola isn't the "true" first worker-placement game by whatever completely bastardized definition of that term BGG is using today.) Two "Bidding" games can feel very very different. Two "Area Majority" games can feel very very different. But with few exceptions, Worker Placement and Deck Building games are designed like "Plus Alpha" games. If I can teach a game in two minutes by saying "You've played Dominion? Okay, this is like that but..." then there's something... well, maybe I don't want to say "wrong" but something strange.
In music, "plus alpha" often occurs when fanbases want to make their favorite band's next album for them. Some good music can come out of this, and some healthy, vibrant, interesting "scenes" can develop out of this. One good example is the recent "Midwest Emo Revival" where many bands have latched onto a certain style of music and (with relatively little variation) keep producing competent albums that sound a lot like the next album American Football or Mineral might have released. I won't say what they're making is bad music; I quite enjoy a lot of it. I'm not even concerned that it's derivative, and don't resent the creators for having influences. But when you set out to design something but you already have the blueprint in mind, you are not really doing much of the designing. As such, you're unlikely to make anything new or amazing. But you can make something that's okay.
People latch onto "Plus Alpha" because of the familiarity. With games, this is doubly true; players of Shootman already have most of the skills needed to competently play Shootman plus alpha. This cuts out the unpleasant part of a game's learning curve where the player does not get to feel competent, however, as a result games become more and more reliant on skipping that part of the learning curve, widening the gap between newbies and experienced players of the genre. This is visible in FPS and Fighting games in electronic gaming, as well as more than a few examples in board gaming...) Thus, games designed "plus alpha" can become needlessly sloppy, with decisions that an experienced player would rarely, if ever make (buying copper, for example) hanging out in future iterations of the design and acting as a familiar competence for experienced players as well as a barrier for newbies. That's probably fine, a game doesn't need to be easy for newbies to be okay.
"Plus Alpha" game design is an easy way to make okay games, and that's what makes it so dangerous.
This style of game design has plagued recent AAA titles in video-gaming because from a business perspective it makes a lot of sense. It's low-risk, high reward. Part of what drew me into board games to begin with was the innovation in design; there wasn't really such a thing as 'genre' beyond the theme of the game (or lack thereof). Sure, common mechanisms existed, but those mechanisms were things like "tile-laying" (putting a thing next to another thing) "bidding" (any number of different twists on bidding) "area majority" (most things in a place wins) but those common mechanisms are very, very vague. Agricola and Dominion are the "Doom" or "Wolfenstein" of Board Gaming, (Yes, I'm aware that Agricola isn't the "true" first worker-placement game by whatever completely bastardized definition of that term BGG is using today.) Two "Bidding" games can feel very very different. Two "Area Majority" games can feel very very different. But with few exceptions, Worker Placement and Deck Building games are designed like "Plus Alpha" games. If I can teach a game in two minutes by saying "You've played Dominion? Okay, this is like that but..." then there's something... well, maybe I don't want to say "wrong" but something strange.
In music, "plus alpha" often occurs when fanbases want to make their favorite band's next album for them. Some good music can come out of this, and some healthy, vibrant, interesting "scenes" can develop out of this. One good example is the recent "Midwest Emo Revival" where many bands have latched onto a certain style of music and (with relatively little variation) keep producing competent albums that sound a lot like the next album American Football or Mineral might have released. I won't say what they're making is bad music; I quite enjoy a lot of it. I'm not even concerned that it's derivative, and don't resent the creators for having influences. But when you set out to design something but you already have the blueprint in mind, you are not really doing much of the designing. As such, you're unlikely to make anything new or amazing. But you can make something that's okay.
People latch onto "Plus Alpha" because of the familiarity. With games, this is doubly true; players of Shootman already have most of the skills needed to competently play Shootman plus alpha. This cuts out the unpleasant part of a game's learning curve where the player does not get to feel competent, however, as a result games become more and more reliant on skipping that part of the learning curve, widening the gap between newbies and experienced players of the genre. This is visible in FPS and Fighting games in electronic gaming, as well as more than a few examples in board gaming...) Thus, games designed "plus alpha" can become needlessly sloppy, with decisions that an experienced player would rarely, if ever make (buying copper, for example) hanging out in future iterations of the design and acting as a familiar competence for experienced players as well as a barrier for newbies. That's probably fine, a game doesn't need to be easy for newbies to be okay.
"Plus Alpha" game design is an easy way to make okay games, and that's what makes it so dangerous.