Background jobs question

Question

HI,
Whern I Run get-wmiobject without asjob, one pc return result.
When I run with asjob, both child jobs are failed.
Without asjob 
Get-WmiObject win32_operatingsystem -computername (Get-Content C:\ps\testpc.txt)
SystemDirectory : C:\Windows\system32
Organization    :
BuildNumber     : 6002
RegisteredUser  : human
SerialNumber    : 1234-OEM-123456-1234
Version         : 6.0.6002
Get-WmiObject : ....
+ Get-WmiObject <<<<  win32_operatingsystem -computername (Get-Content C:\ps\testpc.txt)
    + CategoryInfo          : InvalidOperation: (:) [Get-WmiObject], COMException
    + FullyQualifiedErrorId : GetWMICOMException,Microsoft.PowerShell.Commands.GetWmiObjectCommand
with asjob
PS C:\ps> get-job -id 11 | select-object -expand ChildJobs
Id              Name            State      HasMoreData     Location             Command
12              Job12           Failed     False           pc1
13              Job13           Failed     False           pc2

Answer 1

For "Get-WmiObject win32_operatingsystem -computername $env:computername
-asjob":
PS C:\Windows\system32>  Get-WmiObject win32_operatingsystem -computername $env:computername -asjob
Id              Name            State      HasMoreData     Location             Command
1               Job1            Running    False           mylocalpc              Get-WMIObject
PS C:\Windows\system32> get-job
Id              Name            State      HasMoreData     Location             Command
1               Job1            Completed  True            mylocalpc              Get-WMIObject
PS C:\Windows\system32> Receive-Job -id 1
SystemDirectory : C:\Windows\system32
Organization    :
BuildNumber     : 7601
RegisteredUser  : my
SerialNumber    : 1234-OEM-123456-1234
Version         : 6.1.7601