I busted a checkride before getting picked up with SWA. When asked about it during the interview, I explained what happened and left it at that. We talked about the incident for all of 30 seconds.
I wouldn't try to talk about about how you've learned SO MUCH from the experience and how you're SO much of a better pilot because of it. It makes you look like you're trying to hard. Just answer the "Have you failed a checkride" question and move on...
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