"People have always had this craving to have someone tell them the future. Long ago, kings would hire people to read sheep guts. There's always been a market for people who pretend to know the future. Listening to today's forecasters is just as crazy as when the king hired the guy to look at the sheep guts. It happens over and over and over." - Charlie Munger at the 2004 Berkshire Hathaway Shareholder Meeting*
Predicting the future is difficult to do consistently well.
John Kenneth Galbraith put it this way:
"Economists make predictions because they're asked, not because they know."
Valuing a business is necessarily imprecise. Still, with some homework and sound analysis, it's possible to figure out what a business you understand is likely to be worth -- within a range -- and how that value may change over the long run.
It's possible to develop the discipline to always buy with a sufficient margin of safety.
You just have to teach yourself to ignore daily price fluctuations and the noise of forecasters.
* Found under Notes from 2004 Annual Meeting