From a recent news story:
After back-and-forth with Rep. Scott DesJarlais (R-Tenn.), Austin [Defense secretary] admitted that he knew “several hours” after the strike that civilians were killed. The strike occurred on Aug. 29 and the Biden administration revealed civilians were killed on Sept. 17.
There are two possible interpretations of this. One is that they knew some civilians had been killed but assumed they were bystanders, that the vehicle they hit belonged to terrorists and was loaded with explosives. The other is that they knew they had hit the wrong target but did not intend to tell anyone, deliberately lied about it until the falsehood was exposed by the media.
We acted several times on intelligence that we saw, and we were successful on other occasions in preventing attacks,” McKenzie [head of central command] said Tuesday. “This time, tragically, we were wrong.”
On the first interpretation, they used a drone to destroy a vehicle full of civilians in the false belief that it was a terrorist vehicle and only found out when the media told them. If so, McKenzie has no way of knowing how many of the strikes he calls successful were errors of the same sort. They thought this one was a success, continued insisting it was for days after the strike, so could have done the same thing multiple times.
On the second interpretation, McKenzie may know how many of the strikes were successes, how many tragically wrong, but we don't know because when the military makes a mistake they do their best to pretend they didn't. As this time.