The ABC of engineering is "Always Be Creating." Although we might read books, debate practices, criticize existing tools, the core of engineering is to BUILD. The more we build, the happier we will be, provided we take care of two important points.
First, to build does not necessarily mean to code. Coming up with architectures, computational ideas, product design, are still acts of building. Just because it's the striker that scores the goal does not mean the rest of the team contributed nothing.
Second, there's nothing wrong with building what has already been built. It's an important step of understanding. A person who never reinvents the wheel, probably doesn't invent anything new either.