Stigler's law - that is, the fact that eponyms often deny credit for an invention to many people who were relevant for it - is one of the reasons why I try to avoid eponymy where possible.

The other reason is that eponymy is often a symptom of laziness. Rather than finding a good, descriptive name for something, you end up with an eponym that is not at all evocative of the meaning behind it. For example, and without putting too much thought into it, Amdahl's law could have been called something like law of scaling or law of bottlenecks.