Open community approach/Open Source Hardware

In comparison to a download of open source software citizens can just build a version without optimization or they can optimize a product.

Requirements

A user can download the construction plan for the product/hardware and he/she has the permission to adapt the needs of the user.
A user shares modifications and optimizations again with the community, so that other community members can build on the optimization.
Share also dead ends of developments, unsuccessful approaches so that others can learn from these results. Well documented reproducible failure of a development is a valuable source for the next step of development.
Modular transparent reproducible design of a product.

Compare the Open Source Software with an Open Source product like an electric vehicles!
- What is equivalent to the source code in an Open Source product e.g. for an electric car.
- What is equivalent to the binary software (e.g. the LibreOffice suite) in the setting of an Open Source product.
What are PROs and CONs of an Open Source product - (e.g. spare parts, repair, licencing, dependency of companies, licensing concept,...)?
See Wikipedia:Arduino and analyze the combination of Open Source and Open Hardware.
Analyze the licensing model! What does mean for an user of hardware or an developer, if a product was licensed under the GNU Lesser General Public License (LGPL) or the GNU General Public License (GPL), permitting the manufacture of hardware and software and its distribution by anyone.
What are your expectations, if someone releases a product as Open Source hardware? A hardware needs resources to build it and a user has to pay for the required resources. What is the difference to a classical commercial product, where the company does not allow building the hardware by anyone?
How does a modular transparent reproducible design of an Open Source hardware could improve waste management and a reduction of waste?