The smell may have something to do with it though. Have you ever been down wind of a troll?
Yes, indeed. They smell like burnt toast...
But, since I am posting for the original topic, I don't believe that I have ever given a negative vote (or anything lower than a "7" back when that rating system was in (at least not to my knowledge).
I will download a mod, try it out, and if I like it, then I will endorse it, and give the creator tips for improvement. If I like the idea, but I feel that it needs some time to "mature," I will download it, give some feedback, and keep an eye on it, endorsing it when it reaches a satisfactory level of completion for me.
If I don't like it at all, I first ask myself, "Why am I even looking at this mod?" The usual answer is curiosity, but I eventually just close the tab that it is on.