As I mentioned earlier, during times of systemwide stress, liquidity shocks can become correlated so that the same factors that led to liquidity problems for the SIVs could also lead to high liquidity demands in other parts of the financial market, and might also put pressure on banks' own liquidity.
Some banks may not have been fully prepared for the possibility that SIVs would require more liquidity from banks at the same time that the banks themselves would be facing increased liquidity demands elsewhere. The second major factor contributing to recent disturbances stemming from investment vehicles relates to the activities of investors and the role of market discipline.