As a reviewer, the manuscripts that Iddo Friedberg reads usually fall into four categories — the really bad, the really great, the pretty good but needs some fixes, and the ones that need clarification for the reviewer to be able to say whether fixes are needed or not. That last one, says Friedberg at Byte Size Biology, is the most common kind of paper, and often the lack of clarity isn't necessarily due to bad writing but because the method or idea described is so new.