There can be several aliases for a single command.

ls=dir=gci="Get-ChildItem"

But you can't run just run "dir /s". You'd have to say "Get-ChildItem -Recurse" which can be shortened to "dir -Recurse" which can be shortened to "dir -r".

When scripting, you try to use the longform versions. With one-liners, you just sort of fall into whatever paradigm you were previously accustomed to for your first argument.