#2 – The 80-20 Rule (aka “The Pareto Principle”)

The Pareto Principle states that:

“[...] for many events, roughly 80% of the effects come from 20% of the causes”.

Let’s look at some commonly used examples of this principle:

• 80% of the wealth in a country is owned by the 20% richest people.
• 80% of the crashes are mady by 20% of the bugs in your software.
• 80% of the population lives in the 20% most densely populated areas.

The 80-20 division may not be completely accurate for most situations – in some cases not at all – but at least it can serve as a rough guide for typical distributions, and remind us that most things in life is not even!

Basically, the principle claims that a few, select things are VITAL (having a big effect) and a lot of things are TRIVIAL (having less influence).

What this means for game developers

At the fear of overextending this lovely principle, I’d say that it’s very relevant for game developers, at least as a way of prioritizing and thinking about what you’re working on. No matter how much content and polish you put into your game, chances are that players will spend around 80% of the time looking at 20% of it!

But WHICH 20% will they be looking at? That’s the question you need to think long and hard about.

Obviously many players will cover up towards 100% of the areas in a game, i.e. traverse all the levels, and kill all the enemies. However, they will most likely spend 80% of their time in some specific parts of your game, select areas – scattered throughout the game – that make up only 20%. In multiplayer games, most of the action is usually centered around small parts of the maps. These are the kill-zones or chokepoints that developers need to be aware of.

Hopefully the few chunks where players spend most of their time will be nicely done “key locations”, that your team really took time to polish and make cool! Right?

Thinking 80-20

By mentally applying the 80-20 Rule to your work, you can force yourself to think about which parts of your content/features/assets comprise “your key 20%“. The stuff that will make up the larger amount of the player’s experience. This is not just to be found in level design. It might as well be within the core features (like combat, stealth or climbing) that the player uses all the time, or commonly used sound bits, animation, particle effects or GUI elements.

I personally have a hang-up with games where the basic “running animation” isn’t well done. C’mon, developers! I’m looking at that animation constantly, so please make it look good – or at least not so ugly that it catches my eye all the time.

Likewise, it might be the constantly used “explosion” and “gunfire” sounds you need to be aware of. Maybe you should put down that nice, moody soundbite, for a creaky elevator, that you’ve spend 3 days polishing to perfection. If it’s only found in one location of the entire game, it may not be worth the effort, and your time is better spent improving something that the player hears/sees constantly.

What I’m saying is: Make sure the content and core features that the players encounters most of the time are rock solid. That’s what we developers can learn from The Pareto Principle.

“Personal efficiency” and the 80-20 Rule

On a “personal efficiency” level, many people admit that they’re only fully efficient 20% or so of their workday. Those slackers!

Some feel very bad, about this. After a few bouts of double-distilled, crystal clear efficiency they can’t seem to get back on track, and might end up spending way too much time goofing off, surfing the web, writing blog-posts (like this one)…

My advice to you is: Don’t feel bad, it’s perfectly normal!

You probalby get 80% of your work done in those 20% of the day where you are most focused. Getting into the fabled “flow mode” can be hard, but once you’re there you often crank out top quality work. Of course, if you can find some way to stay focussed through a larger part of your workday, by all means do.

My personal experience is that I’m usually (mildly) efficient around 50-60% of the workday, but within those 60% there are “sprints” where I become much more efficient for about 45-60 minutes or so. Those peaks only happen once or twice each day, no matter how much I beat myself up about it.

Your results may vary!

Lastly, I’d like to quote this BetterExplained.com post on the same topic:

… don’t think the Pareto Principle means only do 80% of the work needed. It may be true that 80% of a bridge is built in the first 20% of the time, but you still need the rest of the bridge in order for it to work.

Thanks for reading, and don’t be afraid to spend 80% of your day dreaming up comments for this post.

More Laws of The Universe for Game Designers:

• Part #1 – Karma

Tags: efficiency, game design, Pareto Principle, power law, The 80-20 Rule

This entry was posted on Monday, August 10th, 2009 at 2:53 pm and is filed under The Laws of The Universe (for Game Designers).