Null results often don't mean anything other than insufficient power, poor study design, failure to control for relevant variables, etc. The reasoning against p

Null results often don't mean anything other than insufficient power, poor study design, failure to control for relevant variables, etc. The reasoning against publishing null results is that one cannot prove a null, and therefore there is no finding, AND that the null finding could be due to uninteresting reasons (e.g. sample size). With per-registered studies, there is greater focus on sample size and study design, since the study will get published either way. This balances out the concerns somewhat.