PowerShell Script to remove all permissions for SharePoint user

Threw this powershell script together to wipe out a user from your farm...I have this running in conjunction with other scripts that disable the user in active directory.

Add-PSSnapin Microsoft.SharePoint.Powershell -ErrorAction SilentlyContinue
[Void][Reflection.Assembly]::LoadWithPartialName("Microsoft.SharePoint")

$claimsPrefix = "[Prefix for the user you're removing from the farm]"
$site = New-Object Microsoft.SharePoint.SPSite("[a site]");
$service = Get-SPServiceContext $site;
$site.Dispose();

$upm = New-Object Microsoft.Office.Server.UserProfiles.UserProfileManager($service);

$user = Get-ADUser -Identity [THE USER]

#I use email as the identity in my farm, thus this line

$mail = Get-ADUser $user -Properties mail | Select -ExpandedProperty mail
$profile = $upm.GetUserProfile($claimsPrefix+$mail);

#Delete MySite

Remove-SPSite $profile.PersonalSite -Confirm:$false;

#Delete Profile

$upm.RemoveUserProfile($claimsPrefix+$mail);

$webApps = Get-SPWebApplication -IncludeCentralAdministration
foreach ($webApp in $webApps){

    #Remove explicit rights given in web application policies
    $webApp.Policies.Remove($claimsPrefix+$mail);

    $siteCollections = Get-SPSite -WebApplication $webApp -Limit All

    foreach($site in $siteCollections){
        $spuser = Get-SPuser -Web $site.RootWeb -Identity $claimsPrefix+$mail;

        #Remove from site collection admins
        $site.RootWeb.SiteAdministrators.Remove($spuser);
        foreach($web in $site.AllWebs){
            $spuser = Get-SPUser -Web $web -Identity  $claimsPrefix+$mail;
            foreach($group in $web.Groups){
                
                #Remove from all groups in website
                $group.RemoveUser($spuser);
            }
            if ($web.HasUniqueRoleAssignments -eq $true){

                #Remove any explicit role assignments
                $web.RoleAssignments.Remove($spuser);
            }
            foreach($list in $web){
                if ($list.HasUniqueRoleAssignments -eq $true){

                    #Remove any explicit list role assignments
                    $list.RoleAssignments.Remove($spuser); 
                }#list
            }#lists
        }#webs
    }#sites
}#webapps