The vast majority of non-FISC warrants are also granted. The reason is that prosecutors don't want a reputation for wasting time or getting their evidence overt

The vast majority of non-FISC warrants are also granted. The reason is that prosecutors don't want a reputation for wasting time or getting their evidence overturned. The problem with the FISA court is that it lacks oversight provided by publicly-readable appeals. This, legal scholars have no way to debate if warrants are valid or invalid.