Timing an ordinary event

Timing a familiar event seems straightforward until its boundaries become uncertain. Does the task begin when a button is pressed, when a response appears, or when the next action becomes possible?

Define the start and end before recording the duration. Use the same boundaries for a comparison and note any interruptions. For a short event, the way a person operates the timer can be a meaningful part of the measurement.

Repeat the observation enough to notice ordinary variation without pretending that one result describes every occasion. A clear definition of the event often improves the comparison more than a timer that displays additional decimal places.