What is the difference between VK_ACCESS_TRANSFER_WRITE_BIT and VK_ACCESS_TRANSFER_READ_BIT?

Can you explain the difference between VK_ACCESS_TRANSFER_WRITE_BIT and VK_ACCESS_TRANSFER_READ_BIT?

The standard seems pretty clear here:

VK_ACCESS_TRANSFER_READ_BIT specifies read access to an image or buffer in a copy operation.
VK_ACCESS_TRANSFER_WRITE_BIT specifies write access to an image or buffer in a clear or copy operation.

What more of a difference do you need to see? The standard even links to the sections on copying and clearing.