Sludge

Consider the process you go through when you subscribe to a service. It might be a weekly food box service, a gym membership, or MasterClass video lessons. Either way, the process is easy: enter your information, choose a payment method, and voilà—you are subscribed. If you’re lucky, the first product or session might even be free. Now, consider the challenging process involved when attempting to cancel a subscription. Often, cancelling a subscription requires a tedious phone call, during which you have to explain why you want to cancel while the operator tries to convince you to stick around. This frustrating process is no mistake; it is an intentional design technique known as sludge.

Sludge is essentially the opposite of a nudge. While nudges try to push people to make better decisions by making certain choices easier than others, sludges make a process more difficult with the goal of creating friction, which makes the individual less likely to continue the process. Sludge, however, is not always used to get more money from people or disadvantage the consumer in some way—sometimes, it’s used ethically to encourage people to be thoughtful about their behavior instead of rushing into actions they might later regret. For example, privacy protection requirements can seem annoying, but this friction causes us to think twice about what data we are sharing online and can encourage us to be more careful with it.¹