Forecasting is hard (especially about the future, one might add), but it is made harder when people use inadequate forecasting techniques. If you want to know how to make forecasts, I think there is no better place to start than to read Philip Tetlock’s
The logistic equation isn't quite right because it assumes no growth in the future. Even some kind of modification that has it go to asymptotic is wrong. What actually happens is that things like market share (or maybe share of dividends) tends to stabilize (and it might stabilize at some smaller share than its maximum share). In other words, when something becomes really big, eventually its growth rate slows to that of everything else.
The logistic equation isn't quite right because it assumes no growth in the future. Even some kind of modification that has it go to asymptotic is wrong. What actually happens is that things like market share (or maybe share of dividends) tends to stabilize (and it might stabilize at some smaller share than its maximum share). In other words, when something becomes really big, eventually its growth rate slows to that of everything else.