Trivial arguments are more common than important ones! For instance, let's take a UI designer group. Everyone has their favorite colors, or sizes, or pixels, for things like button placements.
There's also the reverse of nobody warning to deal with complex
things. So often the one that is suggesting goes uncontested.
You can frequently see this even at group projects at school, and such. Perhaps the best
thing to do is to just allocate proportionally to time/importance.
The more close alternatives are, the harder to chose between them. Same thing.