Hotjar uses Snapshots for Heatmaps, Recordings, and Form Analysis. A Snapshot is an on-demand report based on a sample of data. The Snapshot size refers to the number of visitors used to generate a particular report.
So for example, if you start a Recording, the Recordings will stop when the number of visitors defined by the Snapshot has been reached. After this happens the Recordings will automatically stop and you will need to start your Recordings again.
Snapshot sizes for Recordings depend on your plan
BASIC - 100 visitors per Snapshot
PLUS - 2,000 visitors per Snapshot
BUSINESS - 10,000 visitors per Snapshot