Physics

Maximum bubble pressure method

Business

Key (lock)

Action (physics)

Human–computer interaction

Operating system

Interface (matter)

Risk analysis (engineering)

Bubble

Interface design

Parallel computing

Embedded system

Artificial intelligence

Power (physics)

Microcontroller

Control (management)

Process management

Computer science

Interrupt

Quantum mechanics

User interface

Process (computing)

Computer security

Environment and Planning D Society and Space

This paper draws upon the example of High-Cost Short-Term Credit products accessed via digital interfaces and devices to examine practices of interface design and the operation of digitally mediated power. Utilising interviews with High-Cost Short-Term Credit website designers and users of these products, the paper shows how these interfaces are designed and tested to manage frictions: practical, affective or emotional contestations that interrupt or stop users from applying for these products and entering into credit and debt. We suggest that the key role of interface design is to manage these frictions by guiding action in such a way to minimise negative affective states at key thresholds of the application process. The management of friction is enabled by practices of data-driven design, where the contingency of human response is engineered through analytics in order to increase rates of application. Working through the example of High-Cost Short-Term Credit, the paper complicates a notion of control as a smooth or automatic operation of power, instead emphasising the necessity of both continuity and discontinuity as key to modulating action in a digital age. To understand the specificity of interface interactions and move beyond existing work on control, we offer a vocabulary of friction, thresholds and transitions.

Digital interface design and power: Friction, threshold, transition