Occurance of Software Hazard and Mishaps

Occurrence of a software does not necessary result in a hazard or mishap do u agree or not.

Yes, agree. Reliability and safety are closely related. Software reliability uses statistical techniques to determine the likelihood that a software failure will occur. Occurrence of a software failure does not necessarily result in a hazard or mishap. On the other hand, software safety examines the ways in which failures result in conditions that can lead to a mishap.