Not everything normally needs to be saved. However, in this case it looks like the court ordered them to preserve data during discovery and they did not comply. From the article:
Pichai, and many other employees, also testified they did not change the auto-delete setting even after they were made aware of their legal obligation to preserve evidence.
Getting rid of gchat was a crime.
Not keeping records of employees communications though? Honestly who gives a damn? Not everything needs to be saved.
Not everything normally needs to be saved. However, in this case it looks like the court ordered them to preserve data during discovery and they did not comply. From the article:
Ooohhh, that explains it.