Opinions should not be used when deciding to leave negative trust, as for the majority of people a single negative rating can essentially torpedo one's ability to conduct business around here. If you can't cite specific facts and if you cannot speak to why you left a negative rating then it is probably not a good idea to leave such negative rating in the first place.

I would argue Vod leaving negative ratings for MSDN key sellers will have the opposite effect. Potential MSDN key sellers know that all MSDN key sellers will have negative trust so they do not bother checking their trust profile and ignore their trust score. This has allowed multiple people to continue to scam even after having negative trust by selling MSDN keys that do not exist. There have been a number of scam accusations opened against people who received payment for MSDN keys and sent nothing in return and who previously had multiple trust reports saying they had scammed previously at the time payment was received. Normally, when someone starts a business they will initially have difficulty conducting business because they have no reputation, however as they have been in business longer, they will build up a reputation of trading honestly and if they want to maintain that reputation then they will need to not (try to) scam the people they do business with, however when everyone has negative trust ratings this is not possible.

A ponzi is essentially a promise which is mathematically impossible to be kept. A ponzi is essentially a promise that if you give me $1 today, then I will give you $2 tomorrow with no limits as to how much total money I will accept. If I claim to somehow use this $1 and "invest" it for a day that somehow gives me >$1 in returns in that one day, then it is your responsibility to ask questions to debunk my claims if you wish to leave me a negative rating. Take these two threads for example (one, two), they were claiming to "invest" in altcoins/ect. so they were initially given the benefit of the doubt, however after questions were asked and research was done, it was determined they were in fact lying about not being a ponzi and were left negative trust.

Another good example is this in which the OP of this thread was offering ponzi-like returns, however was claiming that he was "investing" money sent to him by "investors" and when he was questioned about how he makes the money that he uses to pay the returns, he provided evidence (not proof) of legitimacy, and without significant evidence that would prove otherwise a negative rating is inappropriate in this case.