Consider the following example. If I sell out-of-money Google calls (say May 590 for $4.40), and GOOG advances near 590 (it is currently at around 550), what do I have to lose if I place a limit buy of the stock at 590? I understand that the moment I buy the shares I would be exposed to the downside, and that I would also have to keep the necessary margin in my account in order to buy the stock. I also understand the opportunity cost due to giving up any upside when I buy the stock to deliver. Other than those considerations, are there additional costs/risks I am missing? If not, it seems to be a reasonably conservative "income generation" strategy (about 10% a year compounded, assuming full margin allocation for each such trade). Sorry for asking what is obviously a newbie question. Thanks.