Antonyms for the phrase "hammering out a deal" might include "failure to reach an agreement," "abandoning negotiations," or "disagreement." Rather than working collaboratively to come to an agreement, these antonyms describe situations where parties are unable to find common ground or give up on negotiations altogether. Other antonyms could include "passivity," "inaction," or "lack of effort," which suggest a lack of motivation or willingness to engage in negotiations at all. Overall, these antonyms emphasize the importance of actively engaging in negotiation processes and working collaboratively to find common ground, as opposed to simply accepting failure or disengaging from the process.