There is a stigma attached to doing a reverse stock split, so it is not initiated without very good reason and may take a shareholder or board meeting for consent. Many institutional investors and mutual funds, for example, have rules against purchasing a stock whose price is below some minimum, perhaps US$5.In an extreme case, a company whose share price has dropped so low that it is in danger of being delisted from its stock exchange, might use a reverse stock split to increase its share price. For these reasons, a reverse stock split is often an indication that a company is in financial trouble.
This could be a good short opportunity :)