The Snapshot can be taken by your whole organisation at once (one report) or by separate business units or functions within your organisation at different times to suit each team (multiple reports).
For example, your organisation may comprise of two business units that wish to take the Snapshot at different times. For this you would require two Snapshot portal logins, two survey PINs and therefore two reports.
This would also apply for an organisation with multiple international locations. Each location would require its own report.