"Forgotten" game mechanics

[Hard Carved Winter]

Reloading forfeits ammo still in magazine
...
Health that doesn't auto refill
...
Cosmetic items as gameplay rewards (instead of microtransactions)
Multiplayer only an optional bonus feature, and not the entire game

You're on to something. 2005: best summer yet!

I kid. It's jarring to see the long list of "forgotten" mechanics that used to be norm. Any one of those would be a notable exception in a modern title.

[Zenorf]

Brain power is a barrier to sales i'm sure... if people can't complete a game, they are less likely to buy the follow up game(s).

That's a fair point. I'd go so far as to say if people find a game hard, complex, or simply alien to their previous experiences, there is a genuine risk of them reviewing it badly in the first place, often stating that "It's just luck" or "You die for no reason" and other such statements. They aren't wrong either, since from their point of view that is exactly what happens, but from a dev point of view it's frustrating and hurts your sales, So there is a definite inclination to go for something easier, and more familiar in order to minimize negative experiences. It's a major concern for large companies trying to cater for millions of end users. It's still a problem for Indies but visibility is still their biggest issue.

I'm saying this from my experiences as a failed Game Dev.

[IceWolf]

My pick would be games with a point-system or high scores like in Pacman, Galaga, or Donkey Kong to name a few. I miss those days of playing games to try and beat your high score so you could have bragging rights with all of your friends. On that note: I miss arcade game "mechnics" too. When need arcades with new arcade games being released to make a come back like in the 80s and 90s.

[Astraea]

Mike
So much agree. I'm pretty sure most puzzle elements in todays games can be completed with ease by anyone with an IQ of 100 or above. Why put a puzzle there in the first place if you're gonna make it that easy? You wouldn't do that unless you want to create an illusion of diversity of game mechanics. While in reality you there's no diversity at all, you can pretty much just walk trough the puzzle.
The guides and forums problem can be solved by just not looking it up, that's more a matter of setting up some ground rules for yourself to get the most out of your game.

I really wonder what made devs change to a one-size-fits-all mold for games. People online that have been gaming for a bit longer complain constantly about how games have degraded yet they keep churning out these abominable games. There's truly good games sometimes and that's a sight to behold when they release, but i'll admit I sometimes buy mediocre games just to have something new to play.

[vawkil]

Not a game mechanic, but rather design philosophy which for the lack of a good description could be referred to as:

The polar opposite of the modern Bethesda "moar huge=moar better" sandbox approach to open world design.

Thankfully someone more linguistically and rhetorically versed already made a video about the very subject, explaining how it's done right using Gothic & Gothic 2 as the prime (and pioneering) examples in this regard:

[MadMummy76]

Brain power is a barrier to sales i'm sure... if people can't complete a game, they are less likely to buy the follow up game(s)..

You'd be surprised how little percentage of players actually finish games. Even with games like Mass Effect that doesn't require much brainpower, the number of players who finish the game is barely more than half. Bioware released statisctics about this a few years ago:

40% of players completed the original Mass Effect,
56% finished Mass Effect 2
42% finished Mass Effect 3
36% beat Dragon Age Origins,
41% Dragon Age 2,

[Sorain]

Not sure if this qualifies as a game mechanic but: Multiple endings and branching based on failure.

Back on the PS1, there was a few games in a little series called Colony Wars. One of the most shocking things to me about playing the first game in the series was when I lost a mission (it was a space flight combat sim.) and the story rolled on. The mission had failed, there were consequences for that failure and the story branched because of it. I barely managed to beat the next few missions and got an ending that wasn't really a happy one but made sense. (basically, my side of the war managed to sign an armistice and get some of their demands met.) I played the game again and beat the mission I'd failed, but then lost another mission on this branch that was totally diffrent and again things branched before I got an ending that was actually worse! (Because this time the enemy had actually felt threatened so their post war retaliation was far more ruthless.) It made getting to the later endings legitimately worth working for, and when the sequel came? I learned it was based on not the BEST ending, but the one I had THOUGHT was the best because the final mission seemed unwinnable. (Colony Wars: Vengeance)

These days if you fail you just reload a save because the plot demands you succeed or you can't possibly succeed because the plot demands you fail. This basic structure, multiple branches and endings where failure isn't the end but changes things? You can apply that to damn near any game with a story. We just don't see it anymore. Imagine if you could start Mass Effect 3 from the ending where Shepard died. That's the kind of massive branching I wish we could see.