More of the usual

It was only a matter of time before one of those IDF shells would in one fell swoop kill a significant number of Palestinian civilians, children naturally among them, and spur the international community to call on Israel to halt the Rafah operation. The Haaretz Web quoted the army as saying that the tank shell in question had "deviated" from its path. What is that supposed to mean? I'm just a tank driver, not a gunner, but I can't recall any instance of this happening during my military service. I guess "deviated" is another way of saying "We screwed up. Sorry for killing the kids."