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If the spell is not countered (because the spell it targets can't be countered), then this card's ability does not put the card onto the battlefield. The spell continues to resolve as normal.
The card is put onto the battlefield, but any effects that check if the original card was "cast from your hand" will not trigger or otherwise consider the card to have been cast from your hand. The card was put onto the battlefield by the effect of Desertion instead.
This spell includes a replacement effect. If the target is an artifact or creature spell, it never goes to the graveyard.
