<prompt> Human: As I grew up understanding the stock market I was told by tv and movies to buy low and sell high. If that is the case,why wouldnt I wait for United Airlines to drop to its lowest today,buy low, then months from now cash out? I am not well versed on how the stock market works,but wouldnt a move like that be encouraged? Whats the downside to investing in a company with deep roots after a minor scandal? Im asking for my education, not to try and make some cash this afternoon.  <response>: Single stock investing is very risky and is generally recommended to only be a very small part of your profile if you want to do it at all. 