There's a clip of John Cleese showing how Beethoven in fact composed the 5th symphony by trial and error.
Google search doesn't find it for me.
Come to think of it, maybe even laws should be tested in a laboratory first. We cannot emulate the human society fully, but some unwanted effects could be detected this way anyway.
As an example, religious conservatives will brainstorm a lot of issues that are bound to rise (according to them) from gay emancipation. In practice, these failed to manifest.
I'm pretty sure same religious conservatives will claim that issues they saw did come up. While the other extreme would just shrug off the same issues as non-issue. Different people value different things... More at 11.
For some professions that might include running some projects at a smaller scale, as a simulation or even as role play exercise
First, establish that a drug binds to the target in laboratory conditions (relatively quick). After that, test the drug in an animal model. After that, proceed to clinical trials, which are phased (phase I, II, III) to first establish whether a dosage exists that is safe (Phase I), what an effective dosage is (Phase II), and only after than testing if it improves upon the current standard of care (Phase III).
Each phase is more costly (both in time and money) than the previous phase and will eliminate a significant portion of drug candidates.
"The success rate of each drug discovery stage in academia was 31.8% for preclinical, 75.1% for phase I, 50.0% for phase II, 58.6% for phase III."
It means giving doctors and nurses simulators, someone to look over their shoulder when learning new techniques, giving them high-quality followup data, finding top performers and make them explain what they do and so on. Which is currently very hard to do, because teaching others means you lose your advantage.
It also means learning from failures of others. That means writing about the fuckups and telling them. Which is currently almost impossible to do, because admitting failure can often result in an end to your career.
And all of this is exacerbated with consolidated, privatized healthcare where the shots are called not by outcome-oriented caregivers, but by profit-oriented MBAs.