Viral loop
Normal use of the product puts it in front of people who are not users yet, such as meeting links, shared files, or invites.
Counts as evidence: The company states that product use exposes or brings in non-users.
Who ran it
Zoom · Free hosts and the invite loop · 2013 to 2016
Viral loop PrimaryThe S-1 says individuals typically start using Zoom when a colleague invites them to a meeting, and attendees who see the benefits often become paying customers.
Zoom · The pandemic surge · 2020 to 2021
Viral loop PrimaryDaily meeting participants, free and paid, went from about 10 million in December 2019 to more than 200 million in March 2020.