A lot depends on the genre of game you're designing.

If you're building a match-3 or mahjong, then you can probably go light on the story, though players still expect something to distinguish your game from the rest. You're not just playing mahjong, your defending the world from the evil Jabberwock who can only be defeated by using the ancient Herring Bone Statue of Salvation whose pieces were scattered and are now guarded by crazed monks who judge a person's worthiness by their skill at matching tiles.

If you're building an RPG, or even a casual adventure game then story is much more dominant.

Other styles of games fall somewhere in between those two one the spectrum.

Telling the story is not easy. First of all, writing is a craft that takes years to develop on its own. In a game, almost everything is told through dialog and some visuals, making it closer to a screenplay or a comic book than a novel. You've got to learn how to develop characters, create scenes that keep the player 'on track' and control the 'pace' of the game, and create meaningful conflicts. I think a lot of people who play the 'story doesn't matter' card are simply afraid of what it will take to make a good story, The other extreme is just as wrong - balance, as in all other things, is the key (even a point and click adventure a la Syberia benefits from general graphics quality, visual scenes, and music).

In short: if you're game is good without a story, it will be even better with a good one.

Edit: You don't need cinematic cutscenes to tell a story. Dialog, along with the natural 'viewpoint' of the game itself, provides you with all the tools you need.

I don't think a strong story is strictly necessary, but it can add a lot depending on the game. A good story isn't necessarily a complicated one, either. You could easily have have chunks of expository dialog (spoken or even text) during a mission combined with mission briefings or tasks, if that.

The original Unreal I think only had an opening and closing cutscene ("you crashed on a planet" and "yaaay you escaped the planet"), everything else story wise was delivered within the game itself, as either things you have to do or text fragments you find.

Ahh, this topic again,

I wrote this long no paragraph breaks post @ the Official C&C Forums a while back explaining in depth this issue, can't find it atm, but essentially:(I'll keep looking)

For a game to have a dedicated community you need both.

My aproach is to develop both in tandem. you want the players to be engaged, weather that means they are following your narrative & characters or just playing a match over and over.

Good story should complement game play, and good game play show why the story exists.

Stories should introduce the themes and choices the player makes in some sort of huministic fashion. While game play illustrates how those choices and actions effect the game.

Ofcourse games have been made to emphasize one over the other, but my point is that games that respect both and try to do justice to both are superior because they fully engage the player.

For example,

Camouflage is a game play feature, and sometimes that's all it is, but if you pair it with with a story about an Assassin/ spy, soldier/ animal then the player not only gets the mechanic your fleshing out, but gets to see why such a feature/ mechanic is inportant for the charicter/ faction. Not to mention the style.

This perspective comes from a person that has spent extensive time on the C&C forums in which this very issue is always up for discussion. Sure C&C was the forefather of the modern RTS gameplay mechanics, however It also included a deep and engaging story for its community.

This is also the line of logic that any artis has, sure you can create a butiful piece of artwork, but does it have a message? is the artist trying to tell you something?

Another way is to think of it another way, there are certain limits in what can and can't be done in specific engines, however there literally are no limits to the possibilities of stories that can be told.

Over time, technology will change and new methods and mechanics for game play will be available, and others will become obsolete. A Good story, if incorporated and told right can be timeless.

Many factors determine the overall story requirement of a game. To be frank, there is no way to justify not having a good story. You can argue the length of the story. You can argue the type, whether this part should focus on gameplay or this part should be more story orientated, there are plenty of things to decide within a story, but a story should always be present.

But let's take a step back, before I go on as to why it is a necessity within all games, first let me explain what I mean by 'games'. When I'm saying games, I'm talking about product quality games, games that you wish to present to the public gaming community. It's different if you're creating a first time game like yourself, and simply want to explore how to make games.

Now, back to what I was saying. Why is a good story, not just a story, necessary? That is because gaming isn't about gameplay. See, this has always been something that upset me when people say gameplay is the most important thing in a game. No, I disagree. The experience is the most important thing in the game. The experience is the collaboration of every single part of the game in order to create, hopefully, one profound game.

This isn't achieved by gameplay alone, where would you be without the sound in your game? it would be empty, you'd have to fill it up with your own music that doesn't suit the atmosphere. What about the animation, graphics, do you want to look at blocks for men? Story is the same, each individual part feels up a void that would otherwise exist within your game. Yes, I argue that even rogue-like games need a good story no matter how small it is.

So, you see where I'm coming from. Good music makes a game a whole lot better then bad music, same with the graphics no matter how thick people like to wear their nostalgia glasses. Good gameplay also, which inevitably leads to a good story.

However, generally a game chooses between gameplay and story. That isn't to say they neglect a side, for example the story will still be good but the gameplay will be great. They pick which one to make better, and in doing so make it the highlight of the game.

So that's why there are story driven games and there are gameplay driven games.

tl;dr a good story is always necessary the same as good gameplay is, however most games make the choice of choosing one and making it great.

A game is a game first.

Uno? Game.

Chess? Game.

Stratego? Game.

Basketball? Game (although it would first be considered a sport)

Hide and seek? Game.

No stories at all.

However, you can use "video games" to tell a story if you please.

I find game mechanics to be most important of all when it comes to games.