This is potatoes.
Want to rage? Read this: https://social.msdn.microsoft.com/Forums/sqlserver/en-US/d77...
Who in their right mind thought YYYY-DD-MM is a good idea. (It's "smart", recognizes the YYYY part and moves it to the end and interprets as DD-MM-YYYY)
The ISO standard specifically used "-" as the delimiter for the standard date format because no one was using it. And MS had to ruin it.