[Utah-astronomy] super massive black hole

I am not sure what I am missing about the unusual nature of NGC 1277 and its' massive black hole. Isn't the purpose of a black hole to feed on its' host galaxy until the meal is finished? So the more a black hole consumes the bigger it gets and the smaller the host galaxy gets. We see this in NGC 1277 and it will be our fate also in the future. Yes? As long as I have your attention what percentage of time does the Universe spend reshuffling and merging of galaxies as compared to existing in a somewhat finished state??? Ron