> Writing automated end-to-end tests? Those are very often best done by those writing the software

This so much - but most of the places I've worked at have insisted that manual testers with zero programming experience should build and maintain the test frameworks. Talk about trying to push a square peg into a round hole. Granted some of the testers have embraced it and not done a terrible job but by and large most of the testers have had no idea and done very little.