Invoice Hard Limits

What is Oracle Development's rationale for allowing revenue to generate (in full or partial) to the hard limit, but not for invoices?  Per below:

Per the Oracle Projects User's Guide documentation:

"When Oracle Projects encounters a hard limit when generating an invoice, it selects expenditure items until the hard limit is met, or until all additional items would cause the hard limit to be exceeded."

"You can partially accrue expenditures against agreements with hard limit funding. You can accrue

expenditure item revenue up to hard revenue limits by partially accruing the potential revenue."

Per Oracle Development:

With the new feature called "Date Effective Funds Consumption" made available in release 12.1, in the case of hard limit funding, Revenue will also be will not split. So in such a case the revenue and invoice amounts will be the same.  Even after this enhancement partial invoicing will not be allowed and is not in consideration for future releases.