Eugene Garfield, who was key to the development of bibliometrics, died in February. Many obituaries testify to his achievements (see, for example, P. Wouters Nature 543, 492; 2017). But I find little of worth in one of the most celebrated outcomes of his scientific investigations — the impact factor. I suggest that the time has come to formally declare this metric's demise.

The impact factor is often used, improperly, to provide a mathematical measure of a scientist's productivity, on the basis of where they published their results. It has proved popular with bureaucrats, and even with many researchers, because it seems to offer an easy way to determine the value of a scientist's output for someone who is either unable or too lazy to read that scientist's papers and judge their true worth (see P. Stephan et al. Nature 544, 411–412; 2017).

It was and still is demonstrably ill-suited to this purpose — as many journals, including those of the American Society for Microbiology, are starting to admit (Nature; 2016). It should never have been used and has done great damage to science. Let us bury it once and for all.