One of the prime features of the free market is that you only have to know that the price does change, but not necessarily the reasons for it.
Money prices are the medium through which the communication of necessary information is made to coordinate effectively the actions of individual planners. As Hayek has pointed out, each particular decision maker does not need to know all the facts pertaining to the changes in resource usage. What is relevant to each is “how much more or less urgently wanted are the alternative things he produces or uses.”  The economic question is always a question of the relative importance of specific things available for the satisfaction of human wants. Each planner does not usually need to know why the relative importance of the things that he uses or produces has changed. What he does need is some indication of the extent to which its relative importance has been altered.
The coordinating function performed by the price system can be illustrated by assuming a sudden shortage of some resource. Those people who will eventually solve the problem of the shortage do not need to understand its cause. The price of a unit of the resource will be driven upward as those who employ it in the most important usages, i.e., use it for the generation of products promising the highest return, outbid those producers who plan to use it in less remunerative products. The shortage has meant that the marginal uses of the resources that could be supplied before the advent of the shortage cannot be provided for as long as the shortage persists. The higher price successfully causes the curtailment of the employment of the resource in its marginal uses. (Thomas C. Taylor, An Introduction to Austrian Economics, 35-36)
…the marvel is that in a case like that of a scarcity of one raw material, without an order being issued, without more than perhaps a handful of people knowing the cause, tens of thousands of people whose identity could not be ascertained by months of investigation, are made to use the material or its products more sparingly; that is, they move in the right direction….I am convinced that if it were the result of deliberate human design, and if the people guided by the price changes understood that their decisions have significance far beyond their immediate aim, this mechanism would have been acclaimed as one of the greatest triumphs of the human mind. Its misfortune is the double one that it is not the product of human design and that the people guided by it usually do not know why they are made to do what they do. (F.A. Hayek, “The Use of Knowledge in Society,” p. 87)
When that occurs with credit expansion (the reason) changing the interest rate (the price change), knowledge of the reason would allow an entrepreneur to make proper investments. The fact that he does not know how much of the lowering in the interest rate is due to credit expansion and how much is due to real increased savings is the reason the business cycle must take place. An invaluable market signal tampered with by government intervention loses its prime quality as a signal.
We have just seen that there are two factors that tend to hold down the rate of interest below the level sufficient to allow for the related elements emerging on the market: (1) The implementation of the price premium lags behind the changes in purchasing power stemming from the inflation; and (2) the additional supply of money thrown onto the market has a dampening effect on the interest rate. Concerning the latter point, it must be realized that entrepreneur-producers are unable to differentiate between additional funds that have been artificially created and additional funds emanating from real savings. (Taylor, 93) [my emphasis]
To blame the entrepeneur for not being able to understand the signal misses the point and misunderstands the esteem Austrians hold entrepreneurs with.
Tom Woods sums up this type of thinking very eloquently:
“If the free market is so great, why can’t it operate without the free market?”