A couple other aspects to these findings that are worth highlighting. The first is, they, generally, these studies are generally limited to what are called interesting tasks, i.e. Tasks that require some creativity, that people have some reason to want to do. No task is inherently interesting. And no task is inherently boring. So, I might not really want to stamp out things on an assembly line all day long, but someone else might find that challenging, to get it right every single time. That being said, there are certainly tasks that are more interesting, generally speaking, for most people than others. Tasks that require some creativity t hat require some thought or problem solving or some ability. Those tend to be tasks that most people think of as interesting. And so the study's about over-justification focus on tasks that start off with some level of intrinsic motivation. Their tasks, that were interesting to begin with at least at some level and reward seem to make them less interesting. Second thing here is that the types of rewards do matter. So, I described a number of different categories of rewards, and the over-justification effect, the demotivating effect, is more true with some rewards than others. So for example, tangible rewards tend to be where the largest demotivating effects happen. Because those are things that are purely substituting something extrinsic. Something external to the activity for the intrinsic motivation that's there. Tangible rewards are the ones that you might think are the best possible rewards, right? We'll give you a bonus or something of value in return for this activity. Those are the greatest risk of substituting for the intrinsic motivation. Conversely, if the reward is unexpected, if it's that surprise reward, hey guess what, we just decided to give you a bonus for your good performance, that doesn't have as much of an effect on intrinsic motivation because it didn't crowd out. When the person was doing the thing, they were doing it for the intrinsic reason and they were surprised by the reward. So random, or chance rewards that come about without expectation don't tend to have as much of this kind of problem. And finally, the other one that's interesting to talk about, performance contingent rewards. So remember, these are the rewards that are based on achievement, actually doing something effectively in the task, can go both ways. If the reward is simply saying, the whole point is the end point, the goal as opposed to doing well, and the person tends to take away from that, that this is really not about me and my accomplishment but this is about some external thing, the performance leve l, then they're demotivating. On the other hand, if the reward is seen as purely informational. It's say, "You did a good job." This is recognizing the fact that you achieve something. Your performance was great. It's all about your performance. The reward is just a marker. Of what you did. Then, we don't see the same effect. Then, there's not the demotivation. And this comes from a variety of papers by Ed Desi and Rich Ryan and they're co-authors that who we're going to meet in more detail in the next segment on self determination theory. This is one in which they did a meta-analysis of over a hundred different papers on effects of rewards. And these were some of the effects that they found on different categories of rewards. So, to dig into more of why this happens and to cut it back to gamification, we need to focus on the underlying theory that explains why certain kinds of intrinsic motivators work and explains what kinds of things actually lead to intrinsic motivation.