A Zorro slot only works as well as the bus controller, and some glue logic which has no checks.
Believe me, the Early Startup will tell you if a board does fail to Autoconfig properly, I have had several dead boards over the years show up. Interestingly, the Amiga does not boot normally when you turn it on with a bad board. It goes right to the board diagnostic screen of the Early Startup, only with a red background instead of the normal grey, and tells you which board is acting up.
