Practical examples of benefits of Prime>
Fail after 5 hours>
Fail after 7 hours
Fail after 9 hours:
Fail after 10 hours:
Fail after 18 hours:
This is why old-school overclockers were calling it good after 24h. But then, it was more about a code of honour, less about posting CPU-Z validations of unstable overclocks.
Stability isn't subjective, but instability is. Many people can live with slight instability. Others, can live with more instability and even more, can live with Prime stable at 30 minutes. Heck, here people run Prime95 for 15 minutes. Ι wonder why they even bother, but just shows how people have changed in their ways.
Prime is slow, but relentless. If there is a minimum instability, it will take its time, but it will find it.