"You can't see all of the issues and all of the problems and how your design really doesn't work until you actually try to build it." - assuming you build something, nobody has tried to build before.

In the 95% of other cases, use a library solutions, read about solutions that exist, try to learn from similar solutions. Don't reinvent the wheel.

It's not wrong to do experiments, learn from that and apply the know-how to production code.