Glossary
Click-asserted progress
Also called click-based completion.
Last reviewed 18 September 2026
Definition
Click-asserted progress is measuring how far a reader got through a course by acts that required a decision from a person, such as a click on a link in the last lesson, rather than by an open, which is an image load a machine can perform.
The reason to define progress this way is that the alternative has stopped working. Apple Mail Privacy Protection loads remote content through a proxy whether or not the reader looked at the message, Gmail pre-fetches and caches images, and clients with images off register nothing at all, so an open rate is wrong in a consistent and flattering direction.
Plan for one in ten to one in four of confirmed readers clicking on the last day, with longer courses lower. Treat the figure as an upper bound rather than a headcount, because security scanners and link previewers press links too.
See also
- Completion rate
A completion rate is the share of confirmed subscribers who reach the end of a course, and for a five-day course measured by a click on the last day it commonly runs between one in ten and one in four, with longer courses lower.
- Open rate
An open rate is the share of delivered messages in which a tiny remote image loaded, used as a proxy for a human having looked, and it is unreliable because that image is fetched by proxies and caches that are not readers and never fetched by clients that block images.
- Mail Privacy Protection
Mail Privacy Protection is the Apple Mail feature that loads a message’s remote content through a proxy whether or not the reader opened it, which is what stopped an open rate from measuring anything about a person.
Read next
This term is covered properly in Email course conversion and completion rates: what to expect, which is a longer piece on the subject.
Every other term is on the glossary index , the longer writing is in the guides, and what this site itself does is on the home page.
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