So, today, we have the Four of Swords. Waite gives this card the following meanings: Vigilance, retreat, solitude, hermit’s repose, exile, tomb and coffin. It is these last that have suggested the design. Reversed – wise administration, circumspection, economy, avarice, precaution, testament.
To me, the imagery of the card tells the whole story. It is a card of rest, and yes, retreat. Tomb and coffin are a bit heavy, as the reader should always leave the querent with a sense of hope, and death and coffins are best stayed away from. Positivity with the cards is key.