A PlosOne review process of one article is worth of sharing. I do not remember the times taken correctly, but all this took very long, several months regardless of continuous asking about the process.
The editor told to each inquiry that he had not found any reviewers. It is good to mention that the manuscript dealt with a rare subject. Even so rare that during the writing, it had been difficult to find ‘enough’ relevant articles to be referred. However, on the other hand, the subject was pretty general and the methods were relatively simple microbiology and, in my understanding, it should not have been so extremely difficult to find any reviewers.
Finally, the reviews came. There were three of those, and none of them suggested rejection. Each of them suggested revision, one minor, and the two other reviewers wrote that the topic is important and emerging. Two latter reviews were of high quality and the reviewers seemed to know about the subject. However, the editor rejected the manuscript. The editor required additional experiments, although he should have understood that this was a field study and not possible to make any new experiments. None of the reviewers suggested more experiments, they suggested minor-moderate changes in writing.
The oddest thing to happen was still to come. It appeared later, that there had been one more review that had been very positive. We came to know about this review, because the reviewer in question contacted the author and told about it. This reviewer had been studying the same research subject. We had no reason to believe that this positive review would not have been on the editor’s table.
The only explanation I can imagine for this is that because the subject was really rare, it could have been presumed that it will gain only few citations in the near future. PlosOne is a journal wanting to increase its impact factor (although all journals want, of course) and therefore, it may keep the possibility to gain citations as one important principle to assess the manuscripts.
Finally, the manuscript was pretty fast accepted elsewhere.
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