3D parts often have thick sections that are difficult to cool. Some sections may freeze quickly, while thicker sections take longer to freeze. This result allows you to see which sections of the part are cooling quickly or slowly.
The percentage frozen layer should be very high, indicating that the part has been cooled sufficiently and has reached a solid state before ejection.
If the part is ejected before it has been cooled sufficiently in the mold, then the part will cool outside the mold and will be prone to warpage.