Utter failure to gain clarity.
It isn't as though I insist that each and every published paper everywhere and anywhere is going to be of substantial value. Sure, there may be a few studies, now and then, that really don't ever contribute to furthering understanding. For anyone, ever. The odds favor this and do not favor absolutes. Nevertheless, it is quite obvious that the "clutter", "signal to noise", "complete story" and "LPU=bad" dingdongs feel that it is a substantial amount of the literature that we are talking about. Right? Because if you are bothering to mention something under 1% of what you happen across in this context then you are a very special princess-flower indeed.
Second, I wonder about the day to day experiences of people that bring them to this. What are they doing and how are they reacting? When I am engaging with the literature on a given topic of interest, I do a lot of filtering even with the assistance of PubMed. I think, possibly I am wrong here, that this is an
essential ESSENTIAL part of my job as a scientist. You read the studies and you see how it fits together in your own understanding of the natural world (or unnatural one if that's your gig). Some studies will be tour-de-force bravura evidence for major parts of your thinking. Some will provide one figure's worth of help. Some will merely sow confusion...but proper confusion to help you avoid assuming some thing is more likely to be so than it is. In finding these, you are probably discarding many papers on reading the title, on reading the Abstract, on the first quick scan of the figures.
So what? That's the job. That's the thing you are supposed to be doing. It is not the fault of those stupid authors who dared to publish something of interest to themselves that your precious time had to be wasted determining it was of no interest to you. Nor is it any sign of a problem of the overall enterprise.
Thoughts on the Least Publishable Unit
Yet, publishing LPU's clearly hasn't harmed some prominent people. You wouldn't be able to get a job today if you had a CV full of LPU's and shingled papers, and you most likely wouldn't get promoted either. But perhaps there is some point at which the shear number of papers starts to impress people. I don't completely understand this phenomenon.
We had some incidental findings that we didn't think worthy of a separate publication. A few years later, another group replicated and published our (unpublished) "incidental" results. Their paper has been cited 12 times in the year and a half since publication in a field-specific journal with an impact factor of 6. It is incredibly difficult to predict in advance what other scientists will find useful. Since data is so expensive in time and money to generate, I would much, much rather there be too many publications than too few (especially given modern search engines and electronic databases).