What’s up with $null in the begin block causing issues in my PowerShell function?

I'm trying to automate account creation for new employees with a PowerShell script, and I ran into a problem that's driving me crazy. In the function I'm building, there's a $null variable in the begin{} block, and instead of just returning my desired PSCustomObject, it seems to be outputting as an array containing a null value along with the PSCustomObject. Here's a simplified version of my function:

```powershell
function New-EmployeeObject {
param (
[Parameter(Mandatory)]
[PSCustomObject]$Data
)
begin {
$EmployeeTemplate = [ordered]@{
'Employee_id' = 'id'
'Title' = 'title'
'Building' = 'building'
'PosType' = ''
'PosEndDate' = ''
}
$RandomVariable
#$RandomVariable = ''
}
process {
$EmployeeObj = New-Object -TypeName PSCustomObject -Property $EmployeeTemplate
$RandomVariable = "Headquarters"

return $EmployeeObj
}
}
$NewList = [System.Collections.Generic.List[object]]@()

foreach ($Line in $Csv) {
$NewGuy = New-EmployeeObject -Data $Line
$NewList.Add($NewGuy)
}
```

I noticed that when I don't initialize `$RandomVariable` as an empty string, my output for `$NewGuy` turns into an array: one element is $null while the other is the PSCustomObject I actually want. Any idea why this is happening? Is it due to treating $null like it's part of a collection, or something with how PowerShell manages scopes?

Edit: Thanks to u/godplaysdice_ for pointing out that in PowerShell, every statement contributes to output, unlike languages like C or C#.