The people doing the rigging were looking to hit targets and get bigger bonuses. There was pressure up and down, depending on personal and corporate positions. There were also issues in terms of perceived stability of the reporting bank - didn't want to quote too high a number or else you looked injured and could be dead within days or weeks.
While the LIBOR (and similar) rate had a huge impact given how many products referenced it, the direct trading is rather smaller and the direct impact of misquoting was small. Rates were moved hundredths to at most tenths of a percent.
Using the billions figure is hyperbolic and doesn't reflect what the people involved did or were trying to do.
If you want to fix problems in important markets, just like in code, you need a clear, detailed, and nuanced understanding of what happened and the motivations of those involved.
And when they were caught... you guessed it, none of those criminals went to jail or suffered any kind of personal responsibilities. The institutions received fines worth a fraction of their profits. Zero incenctives not to do this again. And the world keeps spinning, and we keep getting fucked.
"On 27 July 2012, the Financial Times published an article by a former trader which stated that Libor manipulation had been common since at least 1991."
In other words, this came to light under the previous US POTUS and - much like the crash of 2007 / 2008 - __nothing__ happened. It's amazing how much power the MSM has over the narrative(s) and public perception.
Those companies are international - where is far less important than who. The Obama admin's decision to (effectively) pardon Wall Street (for crashing - and nearly crushing - the __world__ economy) looks even worse. Yeah. I get it. No one likes to hear that their liberal hero BHO screwed them over, in favor of WS, The City, etc.
The point being these financial companies get to operate without fear; without penalty. Which was the nature of the comment that comment was added to.
People were rigging the libor rate to make billions of dollars and nobody was caught for over 20 years
https://en.wikipedia.org/wiki/Libor_scandal