Doesn't help that a lot of commands have the same prefix 'Get-' / 'Set-', 'Add-', etc, so you have to type at least 6 characters, including a '-', to get useful completion.
Personally, I prefer 'ls' for scripts too. I would never use "rd" for a variable name, but since I speak Unix, the more concise 'ls' seems better. To my colleagues without a Unix background, Get-ChildItem, probably is a better choice.
https://msdn.microsoft.com/en-us/library/ms714428(v=vs.85).a...