This theme reminds me of two quotes:

"The burned hand teaches best. After that, advice about fire goes to the heart." (from Lord of the Rings)
"Experience is a good teacher, but her fees are high." (saw this somewhere).

Personally, "allowing failure" is well down my list of preferred options. When people refuse to listen to advice, they do sometimes have to learn "the hard way". The trouble being, of course, that the fallout from "the hard way" may wreak a company, or a career, or careers. One would therefore prefer to avoid it if possible.

Of course, one may be able to pull success from the jaws of failure. And that is pretty certain to make a good story, and many fond memories.

MarkD