Once it is done, you can reformat the disk or fix the root issue behind it. Firstly, you need to back up the existing data on the disk as it might stop functioning anytime. Ideally, it doesn't take a lot of effort to fix the Disk Utility can't repair disk issue. Steps to Fix the "Disk Utility Can't Repair This Disk" Error The disk might have a bad sector or could be corrupted by a malware.
The data in the disk could be corrupted.The disk could be removed while performing the first air operation.You might be running an outdated version of macOS.
Part 3: How to Recover Data After Mac Disk Repair?.Part 2: Steps to Fix the "Disk Utility Can't Repair This Disk" Error.Part 1: Why Disk Utility Fails to Repair a Disk?.