There was a designer back when I was in college that talked about this, and I don't know if he was summarizing another quote or giving his own, but I remember him describing the problem of dream projects (roughly) this way:

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Sometimes if you're a creative person, you have a vision in your head about what you want to make. The problem is, you also can see when the things you make aren't quite measuring up to that vision. And so when you make things, you look at them, and they don't match the vision in your head, and you get very discouraged.

The danger is that thinking about the things in your head becomes more attractive than building them. The danger is that you never actually try to build the things because building them is miserable and thinking about the theoretically perfect dream in your head becomes more satisfying then engaging with the messiness of actually trying to construct it; particularly if you know that what you construct won't perfectly match that vision. When you know up-front that the thing you want to make is going to be messy when it's in reality, it starts to feel safer to just not have it be in reality, to only think about the theoretical finished product.

And if you fall into that trap, you'll spend a lot of time thinking about what you want to build, and no time ever building it.

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That could be a longer conversation, but the short version is, I personally think there needs to be a mixture of "I'm going to produce something imperfect and I'm OK with that" and "I'm going to produce a lot of imperfect things and get better at this so it's less theoretical."

There are problems that can be solved by looking up resources or practicing, but there are also problems and skills where you won't even know what to practice until you start doing the thing and identifying issues that you didn't know existed. In particular I think about stuff like writing; if you have a theoretical idea for a novel but you don't think you're a good writer and you don't know how to publish -- those are not easy problems to solve unless you sit down and write things and try to publish things, and make mistakes and start to understand what specifically you need to practice.

Maybe that means taking a shot at the project with the expectation that you're going to fail, and then saying, "well, okay, I've learned X, let's repeat and try it again." Maybe it means tackling different projects and building up to the dream project.

But the trap is where actually working on the project or taking steps to close that skill gap becomes harder than doing nothing. Even small steps make long walks. In some ways, the problem can be looking at the distance and saying "I need to figure out how to cross this distance in one leap." Well, no. What are the skill gaps you have, or what general areas are they in? How can you practice that skill? Do you not really know what the skill gaps are? Okay, fine. Build some terrible stuff and after a while you'll learn what your skill gaps are. Then repeat.