No.... 1) in reality you're constantly investing. nobody invests a lump-sum one time and hopes they chose a good moment to enter the market. the chart gives

No.... 1) in reality you're constantly investing. nobody invests a lump-sum one time and hopes they chose a good moment to enter the market. the chart gives you some idea of your long-term chances. 2) "* if you happen to have invested in a fund that took a nose-dive, hang on to it and don't sell for a long while*" unless it goes bankrupt in which case you definitely want to sell. This is one reason why strategists advocate diversification and investing in index funds: you're sheltered from the (possibly poor) performance of any single company/stock.