There are so many decisions to make. You want to do well, but you're not sure what to do next. Do you start by figuring out what you want to make? Do you start by figuring out what your topic is? What if you do this in the wrong order? Will you waste a lot of time, or worse, fail?
This is really a high school problem. Often, we see students who are so caught up in grades and impressing teachers, that they are afraid to fail or devote too much time on any one project. They need to "get it right" from their first step and this can make the first step very difficult to take. We, as teachers, need to ensure that there is enough support as they start to plan their inquiry and their making. This support needs to happen as part of the inquiry unit itself, but could also be scaffolded through multiple grades to ensure that students have the inquiry, metacognitive, and making skills when they get to more open inquiry like this. My guess is that if we start this scaffolding early enough, we won't be teaching students "new skills," we will simply be making the students aware of their existing play and questioning skills and ensuring that they value them.