VMWare and Windows Defragmentation - The Virtual Machine is slower

It is common to defragment the Windows (the host) without proceeding the VM defragmentation before.
Why?
Because we forget the VM guests when we are not using them.

So, when the VM is opened next time, its performance is slower than normal.
Don't worry.
If the client is Windows, proceed the client's defragmentation.
If Linux, it's rarely necessary. Usually not.
Turn off the VM, shutdown the client, not suspending or hibernating it.
Proceed a second defragmentation using the VMWare's defragmentation command.
By example:

"C:\Program Files\VMware\VMware Workstation\vmware-vdiskmanager.exe" -d "D:\virtualMachines\debian5\debian5.vmdk"
After a successful result, you can finally perform the host defragmentation, and the VM's performance will come back.