The general definitions of "price risk" & "information risk" are as follows:
Price Risk: You decide to risk getting a worse price for the benefit of getting more confirmation/information.
Information Risk: You decide to take a better/early price - however, you may not have confirmation or more information about the setup.
Another way to describe the difference between price risk and information risk is in terms of where you think you have the biggest edge. If you are more confident that your information gives you an advantage, then you can absorb more information risk in your execution (i.e. get in sooner at a better price, before you have confirmation of the market moving in your direction). If you are not as confident in your information, then you cannot absorb as much information risk with your execution and need to take on less information risk by exchanging it for more price risk (i.e. get in later at a worse price after the market has begun to give you confirmation that your hypothesis is correct).
To simplify, either you enter early and get a good price but with little information (information risk). Or you get in later at a worse price but with more information (price risk).
This graph reveals the costliness of waiting for "perfect" information (often referred to as confirmation). Assuming you have a system with a positive expectancy that provided you with a valid entry signal, the longer you wait to take that signal, the potential benefits of that position are greatly lessened (not to mention the increased risk due to the larger stop that is often required). In other words, it does not pay to wait for perfect information.