Verbeek notes that “delegation makes possible a curious combination of presence and absence: an absent agent can have an effect on human behavior in the here and now.”12 In the example of the hotel key ring the manger no longer needs to be present to remind guests to return the key, this job has been delegated to the key ring itself. Another example of delegation given by Latour is a door-spring. “Humans delegate to the door-spring the task of shutting the door after somebody opened it; they inscribe the program of action ‘close the door if it is open’ in the spring.”13 In turn, the design of the door-spring encourages a particular way of using the door; if it is a strong spring then you need to push the door open slowly so that it does not snap back in your face. Products, as it were, “can implicitly supply their own user’s manuals.”14 A different type of delegation can be found in a hydraulic door pull, which is “especially clever [in] its way of extracting energy from each unwilling, unwitting passerby.”15 Here, the door pull delegates to the people using it the task of providing enough energy to close the door tightly.
What things do however is not always so purposefully designed. On top of functionality, on top of delegated scripts and intentionalities, are unexpected consequences. One can “observe more in artifacts than only what is delegated to them, or inscribed in them, by humans. In many cases, that is, things do much more than what humans intend.”16 Using a product can lead to unintended consequences, sometimes positive but also at times undesirable. Examples of products that unintentionally exclude less-abled people are numerous, from revolving doors that keep out wheelchairs to websites that cannot be used with screen readers for the blind. Other less