On at least some platforms it's common to show that progress was disrupted by some sort of an error using special state for progress bar.
For example under Windows (10, maybe earlier ones too) it will make it red and show short animation when state changes (AFAIR, I don't remember exact place where I've seen that, probably Edge or some other browser, perhaps it was just copying files using standard tool or interrupted file compression).
The most common use cases are:

• downloading a file, and showing in noticeable but passive way that it failed;
• compressing archives (no space left on device etc.).

Slightly related ticket: QTBUG-59304.