Preselection employs the default effect cognitive bias – a psychological phenomenon where people tend to go with the option that is already chosen for them, even if there are other choices available. Providers know this and often use it to take advantage of consumers. A common approach is to show a pre-ticked checkbox, though there are various other ways of doing this, including putting items in the user's shopping cart, or pre-selecting items in a series of steps. There are lots of reasons why this is a powerful deceptive pattern. Firstly, there’s simply the matter of awareness - users have to notice it, read it and work out what it all means. If the user doesn't, they'll scroll past completely unaware of the implications. There are other cognitive biases that may be employed in his deceptive pattern. For example, the content may be written to make the user feel that people to feel other people like them would accept the default so they should too (targeting the social proof bias). Alternatively, the content may use an authority figure to pressure users into accepting the default (targeting the authority bias).