What are the settings in the Import dialog, Destination panel?
You are importing 1374 images. Are these images already on a hard drive connected to your computer? If they are you shouldn't have the Move option selected at the top of the dialog window. You should use the Add option.
Since you selected the Move option you also have the option to Rename Files during the move.
In all honesty LR, although it can do certain File Management tasks Okay, isn't the thing you should be using to move images from one hard drive to another and IMHO certainly not during the import process. In your case if you want to move images to some other hard drive than where they are now stored you should do that with the File Manager for the OS you are using. In your case Finder. Then use LR to import those images into the catalog using the Add option to include them in the LR catalog file and leave them where you have them stored.
Change the date format in the import destination to "2016/2016-12-11" to get back to your desired folder format.
In my list of options this is the 2nd one from the top, your current choice "2016/12/11" which is the 7th option.
The / character in the options represents a folder level break for each option.
I just played around with the date formats and that seemed to fix the problem. Oops!