Sorensen Jimmy, Yes it is most important to insert things properly,regarding power adapter these can be a little dangerous as on two occasion whilst using (travelling) I find that because the power adapter are very loose internally, they can become hot therefore cause an electrical problem,shorting out,or trip auto fuse, perhaps this is because of the very loose nature of the internal structure of the adaptors,the fact that we travel extensively and they become loose or are poorly made,most electrical goods are cheap so if you are staying in Japan for long time then you may wish to change to Japan electrical device,forgo the adapter,better to be safe with electrical things.