The other speculators don't. I'm not a stock market analyst but it may be that such analyses will one day become an integral aspect of the film critic's trade. The phenomenon is simply another symptom of the true state of an industry in which costs have risen faster than the inflation rate and most films are flops, but in which the few films that are hits make more money than could have been dreamed of a decade or two ago. The film industry has never been known for its stability, but now it's become the world greatest roulette game with movies instead of chips. The need to win distorts all values, judgements.
Decisions become desperate.
The bigger the profits, the bigger the talent. In each case one smash hit paved the way for a smash failure. What complicates all of this is that, occasionally, one smash hit does lead into another. After all, a movie is a movie. One of the inevitable effects of skyrocketing budgets is to inhibit the imaginations of movie- makers.