Hi Ravi,
Process chain failure may happen because of many reason. Some of them are
- Macro issue
- Data Transfer Process (DTP) Issue
- ABAP Errors ( Space / Memory Issue) --Short Dumps
- User lock issue
- Parallel job overlap
- inconsistencies in Planning area or Transactional data
The below may answer your question why inconsistency happens in Time series
In APO data is stored in two areas
1. DB - is a permanent storage area used for Tables and DP master data (POS)
2. LC - a object oriented DB system, where the calculations happen and where the functions get data with quick access
The data for planning is held in the live Cache database. Data from the DB memory is moved to LC and back depending on the programs and operations performed. The LC uses GUIDs and maps it to the master data in the DB
This transfer of data leads to inconsistency. The consistency check reports aim to take care of these issues
For details please check the link http://scn.sap.com/thread/429219
Thanks
Diana