As a member of the Forbes Finance Council, Casey submits articles for consideration to be published in Forbes. Howard Bailey pays an annual fee to be a member of the Council.

Do you ever ask yourself, “If ‘cash is king,’ why does my financial professional always want me to stay fully invested?” Who does it benefit most?

Your broker might talk about “lazy money” or “dead money” and tell you it’s not doing anything for you -- especially with such low interest rates. But there are several reasons why it’s smart to keep some cash that’s easy to get your hands on when you need it.

How much to hold back depends on where you are in your financial life cycle.