One such simplifying but limiting assumption is that real money balances do not affect aggregate demand directly. Another is that financial intermediation, which is important for credit provision and liquidity creation, has no effects on economic activity and prices other than those resulting from changing lending rates which move in parallel with all market rates.
These people were previously considered unbankable, as they typically do not meet even minimal qualifications to gain access to traditional credit, such as steady employment or a verifiable credit history. Microfinance allows them to generate income and to begin to build wealth and ultimately exit poverty.