At the end of the day, he ran out the Clock and avoided all the principal conspirators.
Acting
When an investigation into a serious matter, and one that is criminal and that had major consequence for the country, turns up no indictments of the major criminal minds, then, it was a major waste of time and money.
An investigation that just points fingers but stops short of prosecutions, is a big waste.
Sort of like what is happening now with republicans pointing out the criminality of Joe Biden and son. Waste of time and money.