Quiesece snapshot creates two delta files

Hi All,

If you take a snapshot of VM (with 1 HDD on it) ---- if you go to ESXi Command line (putty) and to the VM folder and do a ls -lthr *.vmdk

You would only see 1 delta.vmdk (which is the snapshot file) ; Today I realized that when I take a quiesce snapshot and do a ls -lthr *.vmdk ; there are delta files that get created?

Any suggestions why two delta files are getting created

Thanks

Vaibhav