I feel it is well explained here: https://all3dp.com/2/kinect-3d-scanner-easy-beginner-tutorial/

I'm sure at the 3d printing community they can provide a better guide though.

But the guist of it is having a 3d scanner allows you to scan an object that then later you can print (with some editing). This is fantastic for making that broken plastic piece of a machine that otherwise would be working.