In 2011-2012 I had one guy actually consistently take credit for what I was doing because I would work at my place and show up once a week with deliverables (there was a hardware part to the job, and I'd rather use my small workshop built next to my home if I can).
Essentially he told everyone that he was the team leader for the project, and people started to believe him. All he did was walk around the offices and make powerpoints.
He kept telling people that he needed more men and resources to complete the project... all the while, me and another guy were doing good on the project (about on budget, a little ahead of schedule).
Eventually this guy's whining, intended to give him a little empire, is heard by one of the actual bosses. We get called in to explain why we're behind and need more people.
And that's where the crazy thing happens. We show up with the first batch of production devices -- not even prototypes -- and do a full demo, and say "this has actually been ready to field test for a couple weeks now". Great, right? Except... everyone was so used to talking with the douche guy that they didn't really pay attention to us. So we got a dressing down for being late (douche said "it'll take two months for this to be ready to go unless I get two more guys on it"), with the finished product happily beeping and logging data on the conference table!
I felt like Galileo before the Conclave. These were scientists and scientific administrators, believing some twerp's word over their own eyes.
And that's the story of why I quit NASA.