There's another source (I've seen'em do it!). Some computer scientists rehash their papers constantly so almost the same paper gets published in a variety of magazines.
Some? Probably most. A project I worked on produced a "here is what we have just started doing" paper in year 1, then a "we have some more results" paper in year 2, and two slightly different "here is what we ended up with" papers in year 3.
But what do you expect? The system rewards publication above everything. And these are intelligent people. Of course they are going to maximise the numbers. Because if they don't, they get fired and replaced by people who will.
After 10 years in industry (publishing patents, not papers) I contacted my PhD adviser and asked what chance he thought I had of getting an academic job. His answer was equivocal, "none".
I had a professor that spoke fondly of the LPU, the "least publishable unit". And, needless to say, you shouldn't waste more than one LPU on one paper...
(Side note: I was amused to see that the LPU has a wikipedia article. It also references "Salami publishing"... Side side note: I was also amused to see that the acronym LPU also stands for "Lovely Professional University" in India.)
On the flip side I've been working on the same project with lots of progress but no publication for years. There are drawbacks.
I need to graduate at some point and I am afraid my lack of publication will hold me back. I have been working on this project for years and have no feedback from the community. There may be things I've been missing for a long time.
