What is or should be the behavior of PowerShell sink with -Debug or -Verbose switch.

[adzero]

I created a sample script to illustrate the outputs of a logger with both Console and PowerShell sinks :

[CmdletBinding()]
param()

Import-Module -Name PoShLog
New-Logger | 
	Set-MinimumLevel -Value Verbose |
	Add-SinkPowerShell -OutputTemplate "SinkPowerShell : {Message:lj}" | 
	Add-SinkConsole -OutputTemplate "SinkConsole : {Message:lj}{NewLine}" | 
	Start-Logger 
Write-Host "VERBOSE"
Write-VerboseLog "Test Verbose message : ($($VerbosePreference))"
Write-Host "DEBUG"
Write-DebugLog "Test Debug message : ($($DebugPreference))"
Write-Host "INFO"
Write-InfoLog "Test Information message : ($($InformationPreference))"
Write-Host "WARNING"
Write-WarningLog "Test Warning message : ($($WarningPreference))"
Write-Host "ERROR"
Write-ErrorLog "Test Error message"
Write-Host "FATAL"
Write-FatalLog "Test Fatal message."

Close-Logger

When I execute this script with default values for preferences variables and without any switch for Verbose, Debug, ... here is the output :

If I execute the script with a -Verbose switch (or another one), I thought the Verbose level output would be displayed by the PowerShell sink. It isn't whereas the value of the associated preference variable has actually changed to Continue :

If I set the $VerbosePreference variable to Continue before executing the script (or use the -ToParameters switch in ````Set-MinimumLevel``` the verbose log is displayed by the PowerShell sink.

Is this behavior normal ? If yes, what am I understanding wrong ?