Why don't we have SLA for purchasing module instead of Purchasing Account Generator workflow?

Hi,

I could not find Sub-ledger Accounting (SLA) for account generation for Purchasing module (particularly purchase orders and purchase requisition).

I am trying to understand, what could be the reason for Oracle not providing SLA for above entities?

I have gone through the google search and could not find any answer.

http://www.oracleappshub.com/account-payable/procure-to-pay-p2p-accounting-entries/

Thanks,

Srinivas