Was The WWII OSS Generally Ineffective?

I was reading a recent book about “Wild Bill” Donovan-who founded and ran the OSS-which later became the CIA.
According to the book, Donovan was a pretty ineffective manager-his organization never really lived up to the hype. It produced lots of dubious intelligence, and much of the data was suspect-to the point that msot of it was never used.
Donovan was probably sincere-but he was not a good manager, and he (seems) to be given to fantasy.
After WWII, the OSS/CIA parachuted agents into eastern europe-all of them were caght and executed, within a short time.
What did the other allied intelligence units think of the OSS?
The British (MI6) had their own problems, but it seems (from the book anyway), that the OSS was a poorly managed and ineffective intelligence service.

The USA, up to that point, didn’t really have a intelligence and espionage service, so Will Bill had to bascially build one from scratch.

So, sure, it wasn’t great but it was hardly a waste. It did quite good against the nazis, for instance.

I don’t think it was poor management so much as a foreign spy in the OSS that got the agents killed, IIRC. Of course, you can call having a foreign spy in the organization ‘poor management’ but I think that’s being pedantic.