The educated world is built on a web of trust whereupon subject matter experts must necessarily yield to others when something is outside of their realm of expertise. I am a planetary scientist and geophysicist and spent nearly a decade studying. I am constantly learning things in my own field, and by no means do I have a full grasp on every detail. But I can call out BS when someone talks about orbital mechanics or earthquakes or whatever. I do not, however, know anything about the digestive tract of my cat and yield to the veterinarian who has spent their whole life becoming an expert on these sorts of things. I don't argue with the vet that I've done my own research (watched a few youtube videos) and thus am qualified to disagree with them. Because objectively I know less than them on that subject and no cursory review will solve my ignorance.

When rating the bias of news organizations, what qualifications do you have so that you can do your own research? Do you have fundamental knowledge of the journalistic process? Is the media source covering a topic you are a subject matter expert in? Or are you just lashing out because it doesn't vibe with your worldview?