Why aren't files transferred to OneDrive?

Question

OneDrive

Please tell me why when you specify "Autosave - Documents" in the OneDrive settings, that is, when you specify that the Documents folder is stored in the OneDrive cloud and not on your computer, the files in the Documents folder are not automatically transferred to the cloud? Is that how it's intended? Is it intended that the user is first scared shitless that the Documents shortcut leads to an empty folder, and then finds it on his own in C:\Users and copies it to the cloud?