The following four factors for happiness may be useful as the basis for designing user experiences (processes, services, and user interfaces.)

Material in quotes were from SlideShare. Questions are my value-add.

"Autonomy - feeling that your activities are self-chosen and self-endorsed."
What choices are available to the user?
How relevant are the choices to users?
Are the choices tally choices from the users' perspective?
How much of the process can the user really direct and own?
How adaptable is the process to the users' context? Can it be interrupted and resumed?

"Competence - feeling that you are effective in your activities."
How well does the process fit the users' abilities?
How clearly and timely are requirements, instructions and feedback communicated?
What is the tone of the language and visuals used?
Is additional support (such as reference materials and training) needed?
Are reassurances relevant, sufficient and prpvided in a timely manner?

"Relatedness - feeling a sense of closeness with others."
What is the user base like? Is there already a sense of community? What improvements or positive influences can we bring to this community?
What sort of community or networking services are needed around this process?
How can we better bridge connections between users, experts and other relevant parties?
How can we create and maintain a sense of safety (psychological and/or physical) around this process?

"Self-esteem - [the] set point, or [a] person's natural propensity to happiness."
How can we better understand our users?
What can we do to improve our users' self esteem (even temporarily while they are engaging with our process)?
Are we in any way trying to disregard, dismiss or disrespectfully downplay the users' feelings or emotions?

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