The distinction between intrinsic and extrinsic motivation was first looked at by Deci in 1975 and then later he studied this in more detail alongside Ryan in 1985 and 2002. They showed that motivation can be quantified according to the factors that provoke it. When motivation is induced by an external factor (reward, social pressure, approval of a third party, etc.) it’s an extrinsic motivation. Inversely, intrinsic motivation comes from an individual internal factor, driven by an individual interest or desire. For example, if someone exercises to clear their head and to relax, then it is due to intrinsic motivation. Whereas if they exercise simply to join a friend who asked them to go then the motivation is extrinsic.

Depending on the context, either intrinsic or extrinsic motivation can be more effective. Extrinsic motivation is often most effective when engaging someone to complete a simple task. However, when the task is more complicated and might require more in-depth thought and creativity, this type of motivation has been found to be a hindrance. This was clearly shown during Glucksberg’s experiment based on the famous cognitive test “The Candle Problem” created by Duncker in 1945. In this, people were shown in to a room where they were presented with a candle, a box of tacks and a box of matches. They were then asked to attach the candle to a cork board and light it whilst ensuring that none of the wax would fall on to the table below. The solution is to empty the tack box, put the candle inside, use the tacks to attach the box to the cork board then use the matches to light the candle. Tests on this have overwhelmingly proven that when the person is shown the tacks already outside of their box they generally come to the right solution relatively easily, whereas when the tacks are inside their box, more lateral thinking and creativity is required. The interesting point in Glucksberg’s experiment though was the difference that adding an extrinsic motivation to these two test groups made. Participants were split in to two groups: Group A were simply asked to complete the task as quickly as possible whilst Group B was offered the following financial reward: the person who solved it most quickly would receive $150 and others who finished in the top 25% of quickest times would receive $40.

Within these 2 groups, half were shown the more simple scenario where the tacks were already outside the box and the other half the more complex scenario. Results showed that in the more simple scenario, it was in fact Group B who performed the best as the extrinsic motivational tool of the financial reward was very effective for this simpler task. However, in the more complex scenario the results were reversed as Group B found the time pressure and potential financial reward to actually limit their ability to think creatively and find the solution and it was Group A in this case, with nothing other than their own intrinsic motivation, who performed the best.

This principle has many implications for persuasive strategies. For web marketing, it is important to determine which type of motivation will be the most effective in persuading your visitors to complete an action (clicking a Call-to-Action for example). If the requested task is simple enough then adding some kind of incentive or other form of extrinsic motivation could help to increase conversions. If the task is more complex though or asks for a higher level of attention and creativity, it is better to persuade customers through highlighting their own personal interests (autonomy, personal accomplishment, etc.).