Formal credit markets fail in developing economies due to high adverse selection (lenders cannot distinguish borrowers by risk) and moral hazard (borrowers may not repay if stakes are low or enforcement is weak). Lack of collateral and contract enforcement means traditional banking ignores the poor. Credit absence prevents productive investment even for high-return projects.
You already understand adverse selection and moral hazard as information problems that cause markets to malfunction. Credit markets in developing countries are where these problems bite hardest, and understanding why requires seeing how the basic mechanics of lending break down when borrowers are poor and institutions are weak.
In a well-functioning credit market, a bank evaluates a borrower's creditworthiness using credit history, verifiable income, and collateral. If the borrower defaults, the bank seizes the collateral. This system works because information is available and contracts are enforceable. Now strip those conditions away. In a rural village in sub-Saharan Africa or South Asia, most potential borrowers have no credit history, no formal income documentation, and no titled property to pledge as collateral. The bank faces severe adverse selection: it cannot distinguish a farmer with a reliable irrigation project from one who will gamble the loan on a risky venture. If the bank charges a high interest rate to compensate for this uncertainty, the safest borrowers — who know their projects are solid — drop out because the rate exceeds their expected return. Only the riskiest borrowers remain, which is exactly the population the bank wanted to avoid.
Moral hazard compounds the problem on the other side of the transaction. Even if a borrower receives credit, weak legal systems make contract enforcement difficult. A borrower who defaults may face no meaningful consequence — courts are slow, expensive, or inaccessible, and seizing assets from the poor is often politically or practically impossible. Knowing this, borrowers may divert loan funds to consumption rather than investment, or simply choose not to repay. Lenders who anticipate this behavior either refuse to lend or demand prohibitively high rates, shutting out even creditworthy borrowers.
The development consequences are profound. A farmer who could double her income by purchasing a better plow cannot borrow to buy one. An entrepreneur with a viable small business idea cannot finance the startup costs. Savings constraints — which you studied as a prerequisite — mean these individuals also struggle to self-finance, since saving is difficult when income barely covers subsistence and there are no safe savings institutions. The result is a poverty trap: people remain poor not because they lack profitable opportunities, but because they cannot access the capital to exploit them. This is why innovations like microfinance, group lending (which uses social pressure to solve moral hazard), and mobile banking have attracted so much attention — they represent attempts to build credit markets that function despite the information and enforcement failures that conventional banking cannot overcome.