Anyone know what happened here? Or any guesses?

Looks like a couple studs broke off:

https://www.f150forum.com/f38/so-muc...-proof-429064/

 

Bad install.

 

How can a bad install cause the lugs of the spacer to fall off?

 

Over torqued ?

 

Speaking from personal experience from summer 2018 a bad install can definitely rip a stud off. I always change rims on my wifes car from winter to summer and i didnt re torque her wheels this summer and sure enough she calls me to tell me her van was vibrating really badly. She pulled into some stores lot so i drove there to see what happened. First thing i notice is 1 of the lug nuts is gone and the wheel stud is ripped off too. I look at her rim against the rotor and notice theres about a credit card worth of gap. I took her tire iron to the other lugs and they were barely on, took maybe 30lbs of pressure to get them loose. I dont know for sure what caused the OEM wheel stud to rip off like that but i 100% know it was from me doing a bad install on the wheels