I'm not sure I totally understand your goal. I'd suggest something similar to Tyler, but I suggest putting the conditional outside of the loop when possible. Maybe consider a formula field that houses the "answer" and a single Pipeline can set the result to that instead?
Although, I probably would model the data differently (e.g. using child records) so the data doesn't override itself. It depends on your use case and whether you'd like cleaner audit trails!
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Brian
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