The quote everyone knows — I have not failed, I’ve just found 10,000 ways that won’t work — is a later paraphrase. Edison is not recorded saying it.
The documented version comes from his associate Walter S. Mallory, in the 1910 biography Edison: His Life and Inventions. Edison had run over nine thousand experiments on a nickel-iron battery without success. When Mallory offered sympathy, Edison replied: results, why man, I have gotten a lot of results, I know several thousand things that won’t work.
Not the light bulb, and not ten thousand. But the reframe is genuine and it is his: a failed experiment is a result.