openpbs or any work load managers would not know whether jobs have computed successfully with respect to that application or analyze whether the job/app computations are going in the right direction. The work load managers are like postman scheduling the jobs on to the compute nodes based on a policies and do not know/read the contents of the post (job). If the exit status of the application command line is 0 , then success , else job failed. qstat -fx | grep -i exiit . But with an intelligent parser script part of the pbs script , which reads the log output after main application has exited and decides whether it is successful or not and decides the exit code would have some additional dimension to the job runs.
PBS can reschedule jobs onto different node, if a job running on that node has issues or rebooted or node crashed abruptly and many more.
PBS server can be configured for High Availability
PBS supports application level checkpoint and restart
PBS support suspend and resume of a job
These jobs have to be resubmitted again , if they have iterator file or restart file created after interruption, upon resubmission, if the application is intelligent to start from where it was left off when it was interrupted by reading this iterator file, then the application will start to run from that point onwards and not from the start.