That's a really hard question for me. It's mostly a feeling more than a science so it becomes a bit hard to lay it down rationally and I know that doing that will result in weird inconsistencies but if I had to define it, it's probably these three things.

1. The influence of the author or vibe

I find myself thinking that if I associate a particular piece of art as the vision of a single person rather than a collective work, I tend to be more critical of that art or product. Rationally speaking, I know Kagi is made by more than one person and I know the same to be true of Brave but the fact that I strongly associate both to, in my view, very concrete people whose ideology is very clearly shown in the product, it becomes very hard for me to dissociate the product from supporting that person. Of course, if the vibe of the product or art is off, I just don't want to indulge with it - it's essentially an instant turn off. Sometimes it's just a little thing but it lives rent free in my mind.

2. The timeframe

If the person that has an influence is dead, well, I don't have a feeling of contribution to something bad and I might overlook that dislike for the author.

3. The need

If I don't need it and I don't vibe with the author, well, I won't buy it. There's better things out there. On the other hand, if I have no option but to use that product, I might swallow my pride.