"A failure is not always a mistake, it may simply be the best one can do under the circumstances. The real mistake is to stop trying." B. F. Skinner

I'll put this one down to tiredness rather than stupidity. The pictures tell the story, writing the words would be too painful

Part of the floor needed fitting before the correct height for the pine kitchen unit could be worked out. However, some months previously when fitting the sockets...

and all was well with the world