It seems to be rudderless when it comes to giving negative trust marks to people and not making them know where exactly they have mistaken.
If I may ask, do you PM them and let them know their wrong doing? And that is how I would like it to be and not me alone.
Usually, they (DT1/2 members) add an appropriate comment (to explain the reason behind those ratings).
I think not all those who have had negative trust marks are dishonest from my experience.
They're free to try and convince the person that left them those ratings (DT members might make mistakes as well [highly unlikely], nobody is perfect).