The company offered little 'by way of explanation' for the delays. [=as a way of explaining why there were delays]
Some of the more technical terms need/require 'explanation'. [=they need to be explained]
a likely/probable/possible/plausible 'explanation of' how the accident occurred
(..) the trial of the two men... charged with your son's death will be concluded... and seven men and two women whom you've never met... will try to offer you an explanation as to why William is dead. For my part, I've done as much as I can to bring the truth to light. And the truth is this-- (..)1992 A Few Good Men