Is it a common practice to delete the source data for a Pivot Table?
Why do the Pivot Table maintain the data after the source is deleted?

I was trying to reverse engineer a Pivot Table that was created in
2009. I kept seeing the source as a Summary sheet but it was not
listed in the spreadsheet. I thought it was hidden and it was not..
So I experimented a little and created a Pivot and deleted the source
and the data stayed in place but kept displaying the source that did
not exist.

Thanks,
Ty