Don't Let Good Mechanics Create Poor Design

I have found myself in a number of different positions over the years while playing TTRPGs and video games where I come across parts of the rules that give me pause. They're clever, potentially innovative, and sometimes even good. But I never once bother to use them. Let me give you a few examples:

• Alternate Rules: Honestly, some of the best rules that exist in any tabletop game are the ones that get listed as "optional" or "alternate." D&D 5e, in my opinion, would be an infinitely better game if you played with most of the alternate rules in the Dungeon Master's Guide instead of the baseline rules. It would also be an infinitely different game, and I think that's probably why these more creative reinterpretations of the rules are relegated to the discount bin section of the book.
  
  My suspicion is that these were playtested, or at least heavily suggested by designers, but the ideas didn't fully take hold and they were shelved. But in burying these rules in the back of the least read primary sourcebook, it guarantees those rules will never take hold. Not enough people will ever know they exist and we are all creatures of habit. We know what we like, and what we like is what we know. Instead, provide clear direction on desired mechanics and let the homebrewers do what they're going to do anyway. And, perhaps, take a chance on the cool-and-different rules as primary mechanics? We all understand how systems usually work. Many of us are eager to get our hands on something different for a change. Normalize that.
  
  Alternate Rules are often Good Mechanics but Poor Design.

• Not Keeping the Main Thing the Main Thing: If you're building a game leans heavily toward one aspect of design, any part of the game that is not actively contributing to that aspect itself needs to be considered a necessary evil. While it may have to exist in order for the game to be cohesive, it needs to specifically exist in a simple enough manner that it does its job and then gets out of the way. Let's use the D&D pillars here because, while there are certainly many more unique layers you could add to your game, they'll suffice to drive home the point. (D&D claims to stand on the three pillars of Combat, Social, and Exploration.) If your game is primarily designed to get players into combat scenarios and let them fight, nearly all of your game rules and mechanics will go toward explaining how combat works. This is a good thing. The vast majority of questions or misunderstandings will be in how to make combat flow properly and how to interpret those rules.
  
  The issue here is when you go to create Social or Exploration events. You aren't going to go into nearly the depth here, nor should you. Having a full set of rules, intricate details on actions, interactions, additional stats, or games-within-a-game that create crafting mini-games, set up political intrigue, determine whether party members like or dislike you more, or decide just how lost in this swamp you actually are might feel fun. It might give you a chance to flex some amazing new mechanical concepts that you're just certain that everyone will love. But I assure you, if the rules of these side options throw out the base game mechanics you've already drilled into the players' heads, they're going to attempt them once or twice and say, "Well, that was fun. Back to the real game!"
  
  The way to integrate these systems into the larger game as a whole are to ensure they follow a recognizable mechanical structure. If a player who's used to combat with 6 second rounds, d20s to attack, and success-or-failure-only mechanics is faced with subsystems that are nebulous in time, require dice pools or d100s, and are told they can kinda succeed on things but it'll take longer to accomplish, that's confusing. Build that same subsystem with the same mechanical structure they're used to (with clever modifications as appropriate) and it will immediately feel familiar, despite never actually being used before.
  
  Unrelated game rules for lesser-emphasized subsystems are often Good Mechanics but Poor Design.

• If a Game Isn't Designed to be a Collectible One, Don't Make it One: Does your game have an emphasis on crafting magical items or upgrading gear with discoverable trinkets? Delicious food comprised of delectable ingredients? Special trophies from defeated enemies that grant special abilities? All of those things sound amazing and I'd love to try them out. But if they're minor add-ons to a larger game that isn't really about that, it may instead give me pause. Do I actually want to go on fetch quests to acquire crafting materials? Do I really need that one food item to give me a bonus and can I instead buy it from a vendor? If there's a really cool concept that you're looking to add to a game and it feels like it may actually be able to exist as its own game--chances are it would be better as its own game.
  
  Whether it's a 12-hour main story plot for a video game that turns into an 80-hour saga because you've got to find all the special doggo tokens, a survival game where you've added so many mods that you need to double the storage chests at your base to hold all the item drops (and return to base twice as often because inventory's always low!), or a game that requires constant monster grinds to get rare gear/component drops only 10% of the time, what you're doing is sacrificing the opportunity for true story and supplanted it with gamified repetition. While some video games can get away with the grind for awhile, no TTRPG campaign can survive this. Pokemon is designed around collecting things. It's arguably more the intent than defeating the gym bosses. But unless the real treasure of your game are the satchels of rare wyvern scales you collected along the way, perhaps it's time to rethink whether a party is actually going to find it enjoyable to climb to Mt. Doomb and harvest five rare Tigerlily blossoms under the light of a blood red moon. For the third time this campaign. Save those incredible design ideas for a game that can actually lean into the concepts, instead. Because there are folks who would get more excited to play that if presented on its own.
  
  Collecting special items scattered across the world are often Good Mechanics but Poor Design.

What examples of Good Mechanics/Poor Design have you encountered in your gaming career? Let us know!