Courage to share risky ideas

I and my new trainee discussed his idea about how to optimize our job feeds integration process [that my trainee learns].
The trainee's optimization idea turned out to be incorrect [which is unsurprising for a newbie].
I talked about a balance between our desire to learn from new suggestions vs our desire to avoid spending time on discussing too many mistakes.
My recommendation range: definitely more than zero suggestions per day, but less than several hundred incorrect suggestions per day.
My trainee had only several suggestions today, but he felt that he suggested too much.

My follow-up message to the trainee:
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Please remember how you incorrectly predicted whether you are oversuggesting or undersuggesting.
You thought that you are oversuggesting (too many mistakes), but, actually, you are undersuggesting (too few suggestions).
That mistake [of being too cautious] is typical.
You frequently will feel that you are making too many mistakes in your suggestions. That feeling is incorrect. You should watch for that "what if I am wrong?" bias and remind yourself that you should discuss your ideas even if your ideas are likely to turn out to be incorrect.
Sharing your idea and identifying holes in your idea -- will help you to adjust your mental model and generate better ideas in the future.
If you fail to frequently share your ideas -- you will not learn fast enough and is likely to fail at your job.
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