Save contradictory notes to avoid confirmation bias.
The easiest way to say nothing interesting is to put on your horse blinders and march forward, despite any and all evidence that another direction might be best. Cognitive dissonance can be a powerful force. A one-sided argument has nothing interesting to say. Looking at all sides of a situation is the best (and perhaps only) way to find the underlying truth. The world is not black or white, it is both things to different people at the same time. Your notes, and by extension, your thoughts, should be nuanced enough to account for these realities.
You shouldn’t choose what to include in your research and your body of notes based off how well it fits into a pretty picture painted by your own confirmation bias. You should pick out what makes the cut solely on the basis of “does this add to the discussion?”