DBMS_JOB.SUBMIT ORACLE 11g 5 jobs submitted together but 1st job takes unusually longer than rest of 4 jobs although total records processed are same

Question

I am submitting 5 jobs using below code but 1 st jobs takes around an hour more than rest of 4 jobs although number of records processed are same.

loop
  V_SEQID := V_SEQID + 1;
  DBMS_JOB.SUBMIT(jobNUMBER, 'package_name.'||v_process||'('||l_processid||','''||i_currentrundate||''','''||l_userid||''','''||automanualflag||''','''||l_machinename||''','||i_seqid||','||v_seqid||','||v_min||','||v_sequenceidto||','||v_Batchno||','||G_batch_seq_no||','''||l_tab_delimiter||''');',
                  SYSDATE,
                  NULL,
                  FALSE);
end loop;