Biases in thinking
Reactance
Also called Psychological reactance
When people feel pushed or their choices are taken away, they resist, and often do the opposite of what they're asked.
Pressure triggers a need to prove you're free. A forced update, a hard sell or a nag screen can make people dig in, even against something they'd have chosen anyway.
Offer choices, explain why, and make declining easy. People come round more readily when they feel they decided for themselves.
In practice
An app that forces a redesign on everyone overnight gets a backlash that a gradual, optional switch would have avoided.
Common mistake
Faking urgency or scarcity. When people spot it, reactance turns them against the product, not just the offer.
Where it comes from
Described by psychologist Jack Brehm in A Theory of Psychological Reactance (1966).