Post assignment & understand consequences

If you do not make a copy for each student, they will all be working off the same document.  They would be able to see what the other students were inputting into the Slide, Form, or Doc.
Students may also select "File--> Make a Copy"

If you don't give each student his/her own copy of the document, they will all be typing on the same one.

I just did this for my MVCC Students while they were working on their Fairy Tale Rough Drafts.  I created a blank Document titled "Fairy Tale Rough Draft" and gave it a header for them to write their Name.  When I added the Assignment, I made sure that ALL STUDENTS were going to be given a COPY of the Assignment.  This allowed me to check their Rough Draft throughout the Course of the Week, provide edits & comments when necessary, and I could monitor their Progress.  Once they were done with their Rough Draft, they simply clicked "TURN IN" and were finished with the Assignment.  If you don't set it up for Classroom to MAKE A COPY, then you cannot track progress, and they would have to SHARE their Document with you once completed!

When you share a worksheet or any Doc or Slide with questions, you are asked if you want students to be able to edit or make a copy for every student.   I always select the latter.  Otherwise, all students will be working on the same document and can edit/change/delete everything off of your original!  Choosing "Make copy for every student" allows each student to have their very own copy of the original you created.  

Each student needs their own so that they can answer the questions and it does not add to others answers.  It acts like a test for each student

If you are sharing a Google Doc or Slide you can tell the attachment to make a copy for each student. I find this very handy because it creates a virtual worksheet for each student and they don't even have to save it or send it to me. Once they write on it, it automatically gets saved in my Classroom folder on Google.

Each student needs their own copy so you can have each student fill out their own. If you do not submit it as each student getting their own copy it creates a class copy that each student can edit. This is useful sometimes but not for homework or quizzes as each student will be able to view and edit the single document

It is important to make a copy for each student because then they get their own individual copy of the assignment that will be automatically saved into the classroom drive.  If you do not do this, then all students will be editing the same original document in your own drive.

It's important to make a copy for each student because otherwise they are all typing in the same document and that's very counterproductive.

It's also important because if they start typing in your copy then you have to go back to get your original work  and make a new document for it.

Students should have a copy of their assignment so that when they are completing it, it does not change the original.  However, in one class, I created a Google Slides document that I wanted everyone to be working on the same document.  They created a review slides presentation that they used to study from for an upcoming test.