There are multiple reasons duplicate data end up in splunk. The video tries to explain a few of them and steps on how to identify duplicate data.
https://docs.splunk.com/Documentation/SplunkCloud/9.0.2209/Forwarding/Protectagainstlossofin-flightdata
During the video i refer to data storage in splunk as "not in flat files". This was a toung slip and i would like to clarify that data is stored as flat files and what i was trying to say was data is not stored in plain text files which can easily be edited using your standard editing tools.
