Default Bias
Whatever is pre-selected is what most people end up with.
What it is
Changing a setting takes effort and implies a decision. Most people avoid both and keep the default, which makes the default the single most influential choice a designer makes. Set it to what serves the user and the business, and be transparent about it.
The research
Countries where organ donation was the default had consent rates above 85%; countries with the same option but an opt-in default sat below 30%.
Johnson and Goldstein, 2003
How to use it
Default to annual
Pre-select the annual plan with the saving shown. Most will keep it.
Pre-fill from what you know
Location, timezone, industry. Every pre-filled field is a decision the user did not have to make.
Never default the harmful thing
A pre-ticked marketing consent is a default bias people notice and punish.
Related
Sources that shaped this entry: growth.design, Kolenda.io.