How god choose his prophets?

After many years of wandering alone in the desert, having his brain destroyed by

syphilis, Muhammad was completely insane. Near death he came upon a dung beetle that he believed was god. He spent several months talking with the dung beetle before blind luck had him find his way home again. Unfortunately his insane rantings were mistaken for the Words of god, and we have had to put up with that

huge problem for the last 1000 years or so.