I've worked in mid-sized companies where my job wasn't just one thing, and where I was not owned by a project manager. Other concerns existed. Even back at the ancient bank I worked at, our implementation of ITIL recognised this, and put incident and problem managers on equal footing with project managers. If a frequent issue is caused by some underlying problem, that problem needs to be fixed. Working on it was absolutely legitimate. During sprint planning a team could take work from the new features like or the bugs pile without interference from a project manager. If they complained that you worked on a bug, you could lean on the problem manager to talk to the project manager. If the project manager's timelines drift, part of their job is to deal with that, inform stakeholders and extend the deadlines. If they continually fail to factor in the possibility of conflicting work then they suck at their job. If their boss gives them shit for a slipping deadline that was out of their control, then they also suck. In your example the company allocate 100% of your time to working on new features and none of it to maintaining the product or keeping customers happy. There's no point in putting a brand new engine into a rusty car with bald tyres. This a bad organisation.