How to Respond to "We tried something like this before and it didn't work"

What it usually means

The buyer has been burned and is afraid of repeating the mistake. This is a great opportunity: you'll learn exactly what they fear.

Ask what went wrong in detail, then explain specifically what would be different this time.

1I'm sorry to hear that. What happened? I'd like to understand what went wrong.

2What would need to be different this time for it to work?

3That's helpful to know. If we set success criteria together upfront and reviewed them after 60 days, would that reduce the risk?

Adapt the words so they sound like you. Then say them out loud a few times before your next call.