Respondent Fatigue
Respondent or participant fatigue occurs when individuals involved in research or surveys grow bored, tired, or uninterested with the task and begin to perform or respond at a substandard level. Also known as fatigue effects, these behaviors can be intentional (examples would be choosing the same answer letter without reading the questions or stopping a survey entirely) or unintentional. This fatigue can affect the results and possible outcomes of a study so care must be taken when designing questionnaires to ensure they won't elicit any of the negative fatigue effects.