The most common complaint about algorithms is their lack of intelligence, specifically their inability to generate results that match human interactions.
Producing off communication and awkward misses can actually hurt brands more than help them. Perhaps the most publicly algorithm gaffes have been via Facebook social ads, which over the years have served up many publicly noted gaffes. Then of course there is the confusion that automation creates about big date, which for many is just sloppy data.
So, yeah, automation has its issues, but it will improve.