If you're predicting the price of bitcoin will either increase or decrease, you can't have less than a 50% chance of getting it right. There's only two possibilities, even if you're trying to get it wrong, it's still a 50% chance you're right.
How is that ? The price could stay very level for a long time, speculators would be upset at that. Making money from just taking an interest in bitcoin I guess requires some direction, if people setup a business to use bitcoin then they will profit from a very level price. Reason I say that is the stability will encourage use and reliability by its users in the system, very erratic price is actually really bad for business.
If bitcoin went up alot it would likely be seen as expensive then, I dont really agree with it has to be up or down. Its combination of factors, every day the US dollar is changing and its government is taking on more debt with more QE and so on.