I'm currently working with mailbox messages using Graph API. I want to know what does the time in attribute "createdDateTime" indicates?. I'm finding that the attribute "sentDateTime" is ahead for few seconds or equal to "createdDateTime" for a mailbox message.

Graph API response of message:

"createdDateTime": "2021-06-17T13:02:**21**Z"

"sentDateTime": "2021-06-17T13:02:**22**Z"

Another response:

"createdDateTime": "2021-06-15T01:56:**13**Z"

"sentDateTime": "2021-06-15T01:56:**13**Z"

Another response:

"createdDateTime": "2021-06-15T01:52:**30**Z"

"sentDateTime": "2021-06-15T01:52:**15**Z"