What makes reviewing a paper enjoyable?

One more about peer review. To get our papers published, we all have to go through it, and the pleasantness of that experience can vary depending on the reviewers you run into.

But the same goes for the other side. In my role as peer reviewer, I find myself sometimes enjoying it very much and sometimes hating it. Apart from the obvious fact that it is no fun to do it if you have too much work already, what makes the process enjoyable?

Well, papers that are fun to review are the ones that inspire, that present new methods or insights, that make one think "I wish I had come up with that", while bad papers are often formulaic and uninspiring. As for quality, it is a pleasure to review a well written, concise and coherent, high quality paper because it is just a good read and you do not have a lot to criticize.

But interestingly, at least to me there is another peak on the fun/quality graph at the bad end of the spectrum. In a perverse way, reviewing becomes enjoyable again when the manuscript is sufficiently atrocious.

So really the papers that I enjoy reviewing least are somewhere around the middle. The ones that contain reasonably competent but completely uninteresting research, the ones that could actually be good if the authors knew how to write a coherent sentence and develop a clear line of thought, and, crucially, the ones containing overall sound science but a suffocating number of individually minor mistakes. In other words, those that have potential merit but force you to write pages and pages of suggestions on how to make them publishable.

The really hopeless manuscripts make for short reviewer's reports, just like the really good ones. If the science is completely bonkers, it is easy to decide what to recommend. If the entire text is beyond repair, you don't need to bother with making suggestions for individual sentences any more. But most importantly, if a paper is sufficiently bad, reading it can be a very invigorating experience. You may laugh, you may pull your hair, but at least you emote instead of getting bogged down in drudgery.