The quantitative evaluation of scientific research relies increasingly on bibliometric indicators of publications and citations. We present the issues raised by the simplistic use of these methods and recall the dangers of using poorly built indicators and technically defective rankings that do not measure the dimensions they are supposed to measure, for example the “quality” of publications, laboratories, or universities. We show that French-language journals are particularly susceptible to suffering from the poor uses of overly simplistic bibliometric rankings of scientific journals.