Likewise, the less visible opt out option might use a negative suggestion to imply you’re going to miss out on something or are risking bad stuff happening by clicking here.

Because humans hate being bored or confused and there are countless ways to make decisions look off-puttingly boring or complex — be it presenting reams of impenetrable legalese in tiny greyscale lettering so no-one will bother reading it combined with defaults set to opt in when people click ‘ok’; deploying intentionally confusing phrasing and/or confusing button/toggle design that makes it impossible for the user to be sure what’s on and what’s off (and thus what’s opt out and what’s an opt in) or even whether opting out might actually mean opting into something you really don’t want…

What advertising hell on earth is this?

Such as toggles for every single data share transaction — potentially running to hundreds of individual controls a user has to tap on vs just a few taps or even a single button to agree to everything.

The vast majority of WhatsApp users likely never realized they could say no — let alone understood the privacy implications of consenting to their accounts being linked.

“Dark patterns tend to perform very well in A/B and multivariate tests simply because a design that tricks users into doing something is likely to achieve more conversions than one that allows users to make an informed decision,” wrote Brignull in 2011 — highlighting exactly why web designers were skewing towards being so tricksy: Superficially it works.

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