Have you noticed how some games get hype, are played for a while by a huge mass of players only to die after a few months or weeks and never be spoken of again? Whereas others maintain a healthy player base throughout their existence even for many years (or decades)? What distinguishes a successful video game from a failed one?

As a Product Manager, I like to look at games as products. And what makes a great product is a system that propels it. By system I mean the set of actions performed by users and creators that improve the experience and make it more engaging, the more people use it.

Think of Facebook.

In essence, it is a system that relies on users sharing content and rewards them for it with likes, mentions and shares. In exchange, it gets priceless information about them which it uses to increase engagement. For example, every time you share a picture with your dog, people who like it will be tagged as “dog lovers”. Then Facebook will use these tags to show them more content related to dogs: pages, groups, and ads. More engagement means more time spent on the platform — which in turn, means more money for them for their monetization efforts. Remember the iconic “Senator, we run ads”?

How does this translate to games? The more time we spend playing the game, the more money we are likely to spend on microtransactions, season passes, subscription fees, etc.

But in order for a game to have people spend more time in it, video game developers have to design for player retention.

This article will explore the video game design principles for player retention. Mind you, this is purely out of my own observations and experiences.

Sense of progression

It was already half past 1 am in the morning, when John remembered he had to wake up early for a 9 am call with his manager. But he was only 200XP short of reaching another level with his Mage after which he could learn the new, cool Meteor Strike spell. “Ok, just these 200XP and I’m going to bed”, he thought.

Of course, John was late for his meeting.

By showing the player what’s the progress towards their next level, game developers are using what researchers call a Goal-Gradient Hypothesis.

In a study conducted by Columbia University, researchers looked at behavior of coffee drinkers who participated in a “drink 10 coffees, get 1 free” scheme. The results showed that people tended to buy more coffee as they approached closer to their 10 coffee goal.

Likewise, the closer players get to their next goal (character level, cosmetic item, new weapon etc.) the more they will play in hopes of unlocking it.

A prime example of that could be Deep Rock Galactic’s assignment system. To unlock any type of extra reward or weapon, players have to complete a set of assignments-missions. When you’ve completed 3 out of 4 and there’s only one more to go to unlock an awesome plasma cutter — investing 30 more minutes in the game sounds much more reasonable. Even when it’s 1 am.

Design for replayability

Think Chess. And now think Diablo 2. On paper, these two games have very little (or nothing) in common. But in reality, these two games are famous for their replayability — and for different reasons.

Let’s take a closer look at two most important ones: complexity and randomness.

Complexity

Chess is one of the most esteemed and ancient competitive strategy games, played by millions of people worldwide. What makes it particularly special, is that no two chess games are the same. This makes it’s replayability one of the largest draw in for millions of people worldwide.

In fact, many mathematicians tried to compute the number of possible moves in chess. One of them, Claude Shannon, has come up with what’s now called the Shannon number. It is the number of possible chess games based on how many moves each player takes. In a game, where players moved their pieces five times, there are 69,352,859,712,417 possible games that could have been played. All this on a 64-tile board with 32 pieces and 2 players.

Now imagine how many games of Counter Strike can be played with dozens of weapons and maps to choose from and two teams of several players. The Shannon number looks bleak compared to that.

This is why competitive multiplayer games are so successful at player retention. No two games of Counter Strike, PUBG or League of Legends have ever been the same, because of the games’ complexity and different player cohorts in each game.

Randomness

You know who replays the same games a lot? Dozens, hundreds, thousand times? Speedrunners.

Speedrunning is a form of a video game play-through where the player tries to finish it as quickly as possible. They do it for fun and challenge, sometimes even blindfolded(!). For example, the world record for speedrunning Super Mario Bros. was clocked in by a Twitch streamer and speedrunner Niftski at 4:54.948 (yes, a little less than 5 minutes!).

Because a lot of them rely on their memory of the game level design and scripted encounters, some of them introduce what’s called randomizer mods. Randomizers are softwares used to shuffle the locations of elements (such as items) to provide an additional challenge to the speedrunner. But what if the randomness could be applied to the entire game?

Enter the Diablo franchise. In Diablo 2 almost everything is randomly generated: maps, items and encounters with magical enemies. There are different kinds of randomness embedded within the game, which this article perfectly explains.

But the bottom line is this: no two gameplays in Diablo 2 are the same, making its replayability a huge factor for the game’s popularity in the 20 years since it’s release. Now, in the age of world-wide AI adoption, the ability for game developers to introduce procedurally generated design in games should allow us to see new levels of randomness.

To summarize, complexity and randomness lend unpredictability to each game session, allowing for higher replay-ability. Succeeding in keeping players surprised plays a crucial role in increasing engagement and retention of a game.

Competition

Roger Federrer vs. Rafael Nadal in tennis. India vs. Pakistan in Cricket. Pepsi vs. Coca-Cola in soda. The biggest rivalries in the world ignite the imaginations of whole generations. And as research suggests, competition makes us work harder and stay more motivated regardless of the objective stakes.

The more the effort put into competition, let’s imagine a League of Legends match, the higher the reward. And this entails both the goodies and experience received in game, and also the dopamine shot into our brains. In his book “The Winner Effect” Dr Ian Robertson of the Trinity College in Dublin, argues that the reason people are so happy when they win, is due to chemical reactions.

“Winning increases testosterone, which in turn increases the chemical messenger dopamine, and that dopamine hits the reward network in the brain, which makes us feel better.” Source.

The reward is even higher, when rivals are of similar skill and motivation.

For game developers this means they have to create a competitive environment in which they match players of similar skill, but also make sure they win from time to time against weaker opponents.

This way their rivalry ensures they are invested in the game and if they fall ever too often — wins will put them back on the right track in terms of motivation.

MOBA games like League of Legends or Dota 2 are prime examples of that. The matchmaking algorithm’s reward function is keeping most of the player base at a 50/50 win ratio to keep the difficulty at the right level.

A lot of games group the players in “leagues” with different rank systems to ensure they compete with people on the same skill level. Ranks are an excellent example of how a sense of progression boosts competition (and vice versa).

The video game retention flywheel

So how do sense of progression, replayability and competition come together to save a game from dying out?

Think of them as parts of a flywheel, where each element acts as an input to the next one, spinning the entire system.

Replayability makes people play the game over and over again.

This boosts their sense of progression — they score higher levels and obtain new rewards.

When progress is measured — players can compete with each other, leading to an increase in replayability.

Each feature unlocks the next one:

Competition is meaningless without a way to compare to other players. And when an activity is meaningless, people stop doing it. It’s like playing football, but not keeping score. Yeah, you can play once or twice, but with no clear indication of who has won it will become boring pretty quickly.

Conclusion

Of course there are more aspects to video game retention. Customisation of avatars, designing the game to be easy to play and hard to master or supporting the community. However, replayability, competition and sense of progression are essential to keep a game alive and make sure gamers will come back to play even more.

In turn, for game developers this unlocks various monetization techniques, allowing them to keep the game alive and fun for longer.

Let me know what you think!

PS: Special thanks to my beloved gf who watches me game every night instead of spending time with her and then has to proof read an article about gaming in her free time.