This does not quite match destructive conditioning, but is a general and ceaseless recitation of how failure is imminent, the company is bad, the solution is bad, the food is bad, their feet hurt – there is no shortage of whining. Unhappy people sometimes find themselves in jobs they hate, and some negotiators are very unhappy people. They may drag us down with them if we are tired, hungry, or prone to negativity ourselves.
Examples are people who seem to be carrying around their own gloomy raincloud, saying things like, “This will never work” or, “We’re never going to find a solution.” They are not pointedly or personally cruel, but are impossible to please.
Resist with (figurative) flowers, rainbows, and kisses. The negative party may very well be depressed, so do not fault them for an illness. The good news is that very few people can maintain oppositional negativity in the face of overwhelming positivity, so become an overbearing beacon of happiness. It really works. Fictional lore is full of such examples because truth is stranger than fiction.