I installed some used cleats that had around 100 miles on my new Giro Apeckx shoes.
I went out on a test ride around 6 miles. On the way back home I started sprinting, and I felt my foot pull up from the pedal. I pulled over and noticed my right cleat was not on my shoe anymore. The cleat was stuck on my pedal and the bolts were still attached to my shoes.

Was this a cleat failure? Bad/cheap cleat?

I did install the cleats with the shorter cleat bolts that were provided with the shoes due to the low-stack height.