look at all the fun that happens

mdbug.ps1

workflow Test3 {
    param (
        [parameter()]
        [String]$Number
    )

    Start-Sleep -Seconds 10
    if ($Number -eq 'One') {
        return 1
    }
    
    if ($Number -eq 'Two') {
        return 2
    }
}

workflow Test2 {
    param (
        [parameter()]
        [String]$Number
    )

    $returnValues = Test3 -Number $Number
    $output = "$Number : $returnValues"
    Write-Warning $output
}

workflow Test1 {
    $index = 0
    do {
        $tests = @('One', 'Two')
        ForEach -Parallel ($test in $tests) {
            Test2 -Number $test
        }
        $index++
    } while ($index -lt 5)
}
  
Test1