Being only a passive observer of futures markets since late last year, I did not, fortunately, have to pay a monetary price for admiring and believing my favourite 'gurus' : Jim Rogers and Marc Faber.
Had I had an active account since late 2009, I would most likely(and most conceivably) have blown my balance going long on agricultural commodities like Wheat
and Sugar.
I actually entered a long position in my Virtual Trading account in late December @ 538.5 and was sitting on a nice profit as the market rallied to about 575 by early January, feeling pangs of regret at not expediting my account opening.
That sentiment ended as abruptly as the about-face in the grains complex started shortly after, dragging Wheat to 468 currently, and also almost all members of the Grains complex with it.
Sugar fared even worse, as it broke all supports as the price collapsed 33% from $30 to briefly below $19 recently(chart below).

(My pet Chihuahua named 'Sugar' grew fatter than ever in direct contrast over the period. Not that I'm complaining as I love my pets fat and furry)
Make no mistake: My convictions still lie on the side of 'ol Jim and 'ol Marc.
However, I no longer worship any one investor as a 'God' as some peoples' timing may be slightly off.
And the slight deviation in timing, in these volatile investment environments, can make all the difference!

