Speak to free-to-play detractors, and many will argue that the model reduces games to mere Skinner Boxes, with titles designed to trick players into parting with their cash after being treated to enticing rewards.
For those unfamiliar with Skinner Boxes, they work by rewarding subjects (in B.F. Skinner's time, lab rats) with food for pressing the correct lever when stimulated by a bright light or loud noise.
Replace 'food' with 'gems', and 'lever' with 'touchscreen' and it's easy to see why the model can be applied to many high profile free-to-play games. However, just because the model fits - and, for a time at least, offers success - doesn't mean it's the only option.
Indeed, for GAMESbrief founder and author of The Curve: From Freeloaders into Superfans Nicholas Lovell, many players are eager for developers to move on.
We caught up with Lovell at GDC Next in Los Angeles for his take on free-to-play's next steps.
Pocket Gamer: Let's start by talk behaviourism. What's the traditional line of thought that convinces developers to view games as Skinner Boxes?
Nicholas Lovell: Firstly, a disclaimer: I am not a psychologist, and have a layman's understanding of Skinner Boxes.
Skinner boxes - more accurately called Operant Conditioning Chambers - originated as an experiment by psychologist B.F. Skinner to investigate how test subjects, typically rats and pigeons, could be encouraged to display certain behaviours if they are given suitable rewards.
A rat might press a lever and get a reward, or have to press that same lever ten times to get a reward, or press it once with a 10 second period and so on.
Skinner found that introducing randomness into the process, both in terms of the size of the reward offered and the activities that the test subject was required to complete, led to the creature to repeat the action over and over again, to the extent of injuring themselves.
One conclusion is that it is possible to use a variable reward structure to encourage test animals - and by extension, humans - to act against their own best interests.
Early Facebook games, particularly those created by Zynga, had the look of Skinner Boxes to some people: you turned up, you did a thing, you got a reward for that thing, and you repeated it.
For some players, this was satisfying and enjoyable; to others, it lacked creativity and agency - partly, I think, because they expected a particular type of creativity and agency in their gaming and were frustrated that FarmVille didn't match their expectations.
There are clearly elements of psychological manipulation in Ville type games, but then again, those same manipulations exist in nearly all game designs.
In your talk at GDC Next, you noted that Skinner Boxes eventually stop working because subjects learn there isn't a different possible outcome. Is it fair to say that the success of many 'sticky' games lies in players not coming to this realisation?
I'm not sure that is true. Sure, sometimes a repetitive thing can get, well, repetitive. I enjoyed FarmVille and CityVille and progressed far in them, but when I started CastleVille, it felt very familiar.
In my mind, I projected forward the next three months of grinding and upgrading and mission-completing that I had enjoyed in the previous two games.
That projection took all of five seconds and I concluded I'd already seen all that the game had to offer. I didn't bother carrying on with CastleVille, although of course I might have been wrong maybe CastleVille innovated in ways that I didn't anticipate.
You can level the same accusation at the triple-A approach though, although it does its repetition with more assets, spectacle and unhealthy budget. I finished Uncharted 2, but found it hard to muster the enthusiasm for Uncharted 3.
I expected it to be basically the same action, with a story tacked on top. If it is just about the story, not the gameplay too, then I would rather read a book.
For me, the important bit about Skinner Boxes coming to the end is that you can introduce somebody in the case of FarmVille from a population that's never been exposed to this type of gameplay before, and the "Do something, get reward" thing feels new and rewarding.
Then, when the population is used to this type of idea, just repeating it in the next reskinned game doesn't feel so new and rewarding because the players have started to understand this system.
Skinner Boxes are all about learning stuff, and when you feel like you've already learned that thing the reward is intrinsically less rewarding. Honestly, I'm delighted that the audience is saying "we're bored, give us something new". That's a good thing.
Would you say that 'operant conditioning' in games e.g. the basic slot machine model is sustainable?
There will always be operant conditioning driven games that will work. There will always be a population who likes basic slot machine games, for example. It has a relatively low cognitive load and is an escapist experience.
Ultimately, if it is going to be sustainable, developers need to look at increasing the game experience in three different areas.
Firstly, you can up the spectacle and we're seeing that happening. It doesn't matter so much if you're not learning something new, if you are seeing something spectacular. That's why we're seeing budgets in free-to-play games going up.
Secondly, you can increase the reward level. If players are no longer responding to this behavioural operant conditioning stuff, developers can think "let's ratchet up the rewards." Real money gaming is way of doing that.
Another is the Japanese phenomenon of complete gacha. That's where you ratchet up the rewards but in order to gain the rewards you have to do a bunch of tasks to gain an item.
You repeat this cycle three times again to get four quarters of a lottery ticket just to submit it. And maybe you win, maybe you don't, and if you don't, you start the cycle again.
The nested randomness is very compelling from an operant conditioning standpoint, so much so that the Japanese government has essentially banned it.
Finally, your third option is to do something new and creative. If you are, by background, an analytics-led suit, it's harder to imagine how to do the new and creative than the other two options above, so you'll up the spectacle or up the reward.
Japan recently outlawed the "kompu gacha" practice, which is an extreme example of operant conditioning applied to monetisation. The apparent reason behind the ban was its overwhelming success in parting players from their money. Isn't this a point in favour of operant conditioning for games?
So, okay, you might ask 'why did they bother outlawing it if in my argument earlier it doesn't work?'
Well, it does work, but it works either when it's extreme or it works on a vulnerable section of society. What, I think, the Japanese found was that this double-tier of randomness become so compelling to a subset that it was time for the state to step in and protect some people from themselves.
I'm not a massive fan of state intervention, but there are some cases where people being protected from themselves is important and, by the same token, I don't like the idea of targeting people who are vulnerable. That's morally wrong, as well as being a bad long-term strategy.
So, I'm not arguing that operant conditioning [in games] is totally useless, or that it doesn't work. I'm arguing that at the mass market of 100 million players, simply repeating the same stuff again and again becomes less effective at engaging players because we're not learning or experiencing anything new.
What alternatives does a developer have to the Skinner Box approach if they want to maximise the life-time value of a heavy spender?
I don't think Skinner Boxes drive heavy spenders. My view of heavy spenders, or 'superfans', is that you've got to allow those people who love what you do to spend lots of money on things that they really value.
So, what are the alternatives to operant conditioning? Make people love your game.
One proxy for that is to make people Skinner Box-y addicted to your game, but in actuality, you will have a more successful, satisfying game if people are coming back to it because they want to.
There is recent EEDAR research which says people don't regret spending money if they feel that they've got good value. If they're really enjoying the game, and they want to give you money, give them things to spend on which have emotional resonance for them in the context of the game.
In context of virtual goods, it's emotions that drive spending and a player's sense of value. Players value being a part of something, or standing apart from everyone else. They value self-expression, they value friends and being part of a team, they value their time more than their money, they value any number of different things.
The difference in this approach to a pure Skinner Box which at its most cynical aims to trick the brain into valuing something it doesn't, is that it's about building a social context in which people want to spend money.
So, basically, instead of tricking the brain into valuing something, developers should work on getting players to value something?
And that, to a large extent, means providing a social context. Not necessarily a synchronous multiplayer environment like Team Fortress but in, say, Candy Crush Saga where there's a map where you can see the progress of your friends and you might want to progress faster or catch up to be part of the crowd.
You may enjoy sending lives to each other, which means you understand the value of lives and are happy to spend on them, and so on.
Thanks to Nicholas for his time.