Status hash is a unique key that is generated from values of multiple fields:
Status (passed, failed etc...)
Children status hashes
For more information on these fields check the Calliope JSON format
So if anything changes in a container: A result added, removed, changed, repositioned, the status hash will change as well.
The status hash is used to quickly determine and compare with previous results, so we can distinguish between a result that failed twice in a row, but with a different error.
It can also quickly show if there was a change in the feature.