What's the best way to offer free shipping for recovery?

As a Shopify store owner in the competitive e-commerce landscape, I've been wrestling with cart abandonment and how to strategically use free shipping to recover potentially lost sales. My analytics show that around 60% of customers who add items to their cart never complete the purchase, and shipping costs are often the primary culprit. I've tried blanket free shipping offers, but they were eating into my margins without a targeted approach. I need a smart solution that incentivizes purchases without giving away profit unnecessarily. My goal is to create a free shipping strategy that feels like a genuine value to customers while still protecting my bottom line. I'm looking for a method that can dynamically adjust based on cart value, customer behavior, and purchase intent—something that feels personalized and strategic, not just a generic discount thrown at every potential customer.