Textbook of Usability

Dark patterns are interface designs that deliberately manipulate users into actions they did not intend — subscribing to newsletters through pre-checked boxes, making cancellation flows deliberately difficult, using visual misdirection to steer clicks toward profitable options, or employing "roach motel" designs where signing up is easy but cancelling is hard.

The term was coined by UX designer Harry Brignull, who documents dark patterns at deceptive.design. Dark patterns exploit cognitive biases and perceptual shortcuts — the very same principles this textbook presents as tools for good design — for the benefit of the system operator rather than the user.

Common dark patterns:

• Confirmshaming — guilt-inducing language for the option the company doesn't want ("No thanks, I don't want to save money")
• Forced continuity — easy to start a free trial but requiring a phone call to cancel
• Hidden costs — revealing fees only at the final checkout step
• Misdirection — visual hierarchy emphasising the profitable option
• Privacy zuckering — confusing privacy settings that cause oversharing
• Roach motel — easy to enter, hard to exit
• Trick questions — double negatives and confusing wording
• Disguised ads — advertisements styled to look like content

Dark patterns are increasingly subject to regulation. The EU's Digital Services Act, GDPR enforcement, FTC actions, and California's Consumer Privacy Act all treat dark patterns as deceptive practices. Good usability design uses knowledge of human cognition to help users achieve their goals — not to subvert them.