This paper provides a comprehensive review of the recent evidence on financial inclusion from all the regions of the World. It identifies the emerging themes in the financial inclusion literature as well as some controversy in policy circles regarding financial inclusion. In particular, I draw attention to some issues such as optimal financial inclusion, extreme financial inclusion, how financial inclusion can transmit systemic risks to the formal financial sector, and whether financial inclusion and exclusion are pro-cyclical with changes in the economic cycle. The key findings in this review indicate that financial inclusion affects, and is influenced by, the level of financial innovation, poverty-levels, the stability of the financial sector, the state of the economy, financial literacy, and regulatory frameworks which differ across countries. Finally, the issues discussed in this paper opens up several avenues for future research
Peterson K Ozili (2020) studied this question.