One duffymeg at Dynamic Ecology blog has written a post in which it is wondered:

How do you decide which manuscripts to work on first? Has that changed over time? How much data do you have sitting around waiting to be published? Do you think that amount is likely to decrease at any point? How big a problem do you think the file drawer effect is?

This was set within the background of having conducted too many studies and not finding enough time to write them all up. I certainly concur that by the time one has been rolling as a laboratory for many years, the unpublished data does have a tendency to stack up, despite our best intentions. This is not ideal but it is reality. I get it. My prior comments about not letting data go unpublished was addressing that situation where someone (usually a trainee) wanted to write up and submit the work but someone else (usually the PI) was blocking it.

To the extent that I can analyze my de facto priority, I guess the first priority is my interest of the moment. If I have a few thoughts or new references to integrate with a project that is in my head...sure I might open up the file and work on it for a few hours. (Sometimes I have been pleasantly surprised to find a manuscript is a lot closer to submitting than I had remembered.) This is far from ideal and can hardly be described as a priority. It is my reality though. And I cling to it because dangit...shouldn't this be the primary motivation?

Second, I prioritize things by the grant cycle. This is a constant. If there is a chance of submitting a manuscript now, and it will have some influence on the grant game, this is a motivator for me. It may be because I am trying to get it accepted before the next grant deadline. Maybe before the 30 day lead time before grant review when updating news of an accepted manuscript is permitted. Perhaps because I am anticipating the Progress Report section for a competing continuation. Perhaps I just need to lay down published evidence that we can do Technique Y.

Third, I prioritize the trainees. For various reasons I take a firm interest in making sure that trainees in the laboratory get on publications as an author. Middle author is fine but I want to chart a clear course to the minimum of this. The next step is prioritizing first author papers...this is most important for the postdocs, of course, and not strictly necessary for the rotation students. It's a continuum. In times past I may have had more affection for the notion of trainees coming in and working on their "own project" from more or less scratch until they got to the point of a substantial first-author effort. That's fine and all but I've come to the conclusion I need to do better than this. Luckily, this dovetails with the point raised by duffymeg, i.e., that we tend to have data stacking up that we haven't written up yet. If I have something like this, I'll encourage trainees to pick it up and massage it into a paper.

Finally, I will cop to being motivated by short term rewards. The closer a manuscript gets to the submittable stage, the more I am engaged. As I've mentioned before, this tendency is a potential explanation for a particular trainee complaint. A comment from Arne illustrates the point.

on one side I more and more hear fellow Postdocs complaining of having difficulties writing papers (and tellingly the number of writing skill courses etc offered to Postdocs is steadily increasing at any University I look at) and on the other hand, I hear PIs complaining about the slowliness or incapabability of their students or Postdocs in writing papers. But then, often PIs don’t let their students and Postdocs write papers because they think they should be in the lab making data (data that might not get published as your post and the comments show) and because they are so slow in writing.

It drives me mad when trainees are supposed to be working on a manuscript and nothing occurs for weeks and weeks. Sure, I do this too. (And perhaps my trainees are bitching about how I'm never furthering manuscripts I said I'd take a look at.) But from my perspective grad students and postdocs are on a much shorter time clock and they are the ones who most need to move their CV along. Each manuscript (especially first author) should loom large for them. So yes, perceptions of lack of progress on writing (whether due to incompetence*, laziness or whatever) are a complaint of PIs. And as I've said before it interacts with his or her motivation to work on your draft. I don't mind if it looks like a lot of work needs to be done but I HATE it when nothing seems to change following our interactions and my editorial advice. I expect the trainees to progress in their writing. I expect them to learn both from my advice and from the evidence of their own experiences with peer review. I expect the manuscript to gradually edge towards greater completion.

One of the insights that I gained from my own first few papers is that I was really hesitant to give the lab head anything short of what I considered to be a very complete manuscript. I did so and I think it went over well on that front. But it definitely slowed my process down. Now that I have no concerns about my ability to string together a coherent manuscript in the end, I am a firm advocate of throwing half-baked Introduction and Discussion sections around in the group. I beg my trainees to do this and to work incrementally forward from notes, drafts, half-baked sentences and paragraphs. I have only limited success getting them to do it, I suspect because of the same problem that I had. I didn't want to look stupid and this kept me from bouncing drafts off my PI as a trainee.

Now that I think the goal is just to get the damn data in press, I am less concerned about the blah-de-blah in the Intro and Discussion sections.

But as I often remind myself, when it is their first few papers, the trainees want their words in press. The way they wrote them.

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*this stuff is not Shakespeare, I reject this out of hand