From what I remember in no specific order-
1. Improper Installation blew one motor via a damage fuel line causing a lean condition.
2. A second hand kit pulled from a salvaged car lost oil and damaged the turbine and engine.
3. Most likely a bad tune but yet to be determined caused the motor to be damaged.
4. High rev motor damaged exact cause unknown.
I'm sure there are a few more I don't remember.
Overall blown FI motor are from installation issues then anything else. The majority of people here have the good sense of doing things right.
We are not Honda Civic drivers who buy a FI kit off ebay and install it overnight in our parents garage only to have it blow up in your face the next day trying to be a drift king.