The definition of "match" is complicated, and not just for issues like partial fingerprints and blurring. The FBI says they had a "100 percent match" in the Mayfield case. The judge says this assessment was "fabricated and concocted by the FBI and DOJ".

Or from https://www.science.org/content/article/forensic-experts-bia... published in 2022:

"When police retrieve a print from a crime scene, they consult an FBI computer database containing millions of fingerprints and receive several possible matches, in order of the most likely possibilities. Dror found that experts were likely to pick “matches” near the top of the list even after he had scrambled their order, perhaps because of the subconscious tendency to overly trust computer technology.

“People would say to me fingerprints don’t lie,” Dror says. “And I would say yes, but it’s also true that fingerprints don’t speak. It’s the human examiner who makes the judgment, and humans are fallible.”"