What is 'bait-and-switch' tactic in the context of dark patterns?

The 'bait-and-switch' tactic in the context of dark patterns is a deceptive design technique where a user is lured into taking a specific action with the promise of a particular outcome, but then receives something different and undesirable instead. The initial 'bait' is designed to attract the user and encourage them to engage with the interface, while the 'switch' involves altering the outcome in a way that benefits the company, often at the user's expense. For example, a website might advertise a product at a very low price (the bait), but when the user tries to purchase it, they find that the product is out of stock or that there are hidden fees that significantly increase the price (the switch). Another example is offering a free software download (the bait), but then installing unwanted software or toolbars on the user's computer without their explicit consent (the switch). The bait-and-switch tactic exploits users' trust and expectations, leading to frustration and potentially harmful outcomes.