I've found that the people that seem the nicest are the worst people to do business with. Niceness is often mistaken for not telling the whole truth.

Also, many of those nice people often disappear when the shit hits the fan, because they don't want to be seen bringing bad news. That doesn't fit with the "nice" image they have of themselves.

All things being equal I would rather do business with an honest asshole than a nice person I cannot trust.

Niceness is overrated. Not screwing people over and being "nice" are two very different things.