Comment by echoangle

Thats explicitely stated in the post:

Interestingly I discovered that if the chip is set for unprotected mode, the bootloader actually waits around for update commands instead of booting the application firmware. So Elgato is using the locked/unlocked bit as a way of signifying whether it should stay in the bootloader or not, which I find to be a little bit weird. That completely explained why my second HD60 S stopped working after I installed my unlocked firmware — it was stuck in the bootloader waiting forever because the chip was unprotected.