First, a large commercial bank is a single legal entity, making it hard to provide frequent short-term loans to SMEs in a swift manner. Second, credit rating method for SMEs is significantly different from that of large ones. The current credit risk rating system adopted by commercial banks does not accommodate the operations and accounting information disclosure patterns of SMEs.
The reasons behind this wish are well established so I will not dwell on them: most important of all is the fact that growth feeds on innovation, which is a riskier proposal than proven, traditional productive activity, and it is best to finance innovation with capital rather than loans, especially bank loans,  3  because banks are, and must be, more risk averse than the rest of the financial community.