Also, throw in a healthy amount of irresponsibility. "It's everybody elses fault".
If your retirement funds are in the mkt when you retire it's just dumb. You should be moving those monies into secure (insured) vehicles 7 years before you retire. The only reason not to is you figure you're so smart you will beat the safe bet and get a 7-10% return rather than a 3-4% return.
So a portion of your retirement funds should always be allocated to investments with a 20+ year time horizon. This portion should diminish over time as a retiree ages and needs to become more concerned about safety than growth potential, but good financial advisors will often have their clients keep a small portion of their money in high-risk investments even into their 90s.