The Elephant in the Open-Access Room

Open-access (meaning freely available for anyone to read on the internet) journals are becoming more and more common, with some funding agencies requiring that research financed by them be reported in open-access journals, in the case of public money often justified by the claim that taxpayers have a right to see what their taxes have financed. While few think that open-access journals themselves are a bad idea, there are nevertheless some negative aspects associated with them. I briefly mention a few which are relatively well known then one which I haven't noticed being discussed very much.