I've got a Late 2013 15" MBP (A1398) that has been experiencing random freezes/kernel panics for a while now. I was initially unable to pinpoint a cause.
After a while tinkering and the sudden realization the panics were precipitated by moving the laptop; I realized there is a small screw right underneath the SSD. With time, vibration and possibly hits/falls, the screw can come loose.
The problem with this is the screw's head can make contact on some of the SSD components effectively shorting them out. AFAICT, the shorts are benign and have no consequences other than a kernel panic.
Of course, I wouldn't hold my breath nor bet on it not having the potential to leave permanent damage in the drive.
So... what's the point of the question? This issue can be easily solved by adding one or three strips of Kapton tape (or similar) in order to insulate the screw head from the SSD; as seen here:
This happened to me on the aforementioned model but I wouldn't be surprised if this problem is common to all MBP models sharing this design.