Not all projects have succeeded after they released their own dapp application. It all depends on the developer, you have to innovate and have new features that are embedded in the dapp application. support for updates that must continue to be done to resolve bugs found later.
You are right. at least with the existing app or dapp showing pretty good progress from the development of the project, this is a tangible manifestation of the roadmap. Working products increase investor confidence, this has a positive impact, especially if the product is unique and use case, can be implemented as a whole.
