he seems to be using unix. Windows can be a little inconsistent across the command line tools. I don't know but I believe unix tools try to follow the same way of doing things near universally, but I only use the major ones, there are so many.... anyway, I was speaking from windows perspective
As said, it depends on the path (file, directory, symlink, ...) and the command. There are only a handful of shell builtin commands. Majority are separate applications and they are free to handle their command-line parameters as they like.
For example, rsync copies files and directories. Whether the source (directory) has trailing slash or not changes what is copied.