By the end of day three of deliberations in the Elizabeth Holmes trial, the jury had already decided to find the fallen Theranos founder guilty of defrauding investors who had poured millions of dollars into the Silicon Valley blood-testing startup, according to one juror who spoke with ABC News in an exclusive interview.

And yet, the group grappled for several more days over whether to convict or acquit Holmes — who faced 11 counts of fraud — on three other counts also related to investors, juror No. 6, Wayne Kaatz, said.

“We were very saddened. We thought we had failed,” Kaatz, 64, said, referring to the moment when, hours before the jury announced its verdict on Monday, he and his fellow jurors sent the court a note that they had reached an impasse on those three counts.

Judge Edward J. Davila instructed them to continue deliberating, but by Monday afternoon, the eight men and four women maintained they still could not come to a unanimous consensus. At around 4 p.m., after seven days of deliberations, spanning two weeks, which included Christmas and New Year’s, the jury convicted Holmes on four counts of fraud against investors. They found her not guilty on four other counts, regarding patients who took Theranos blood tests. A mistrial was declared on the counts on which the jurors could not agree.

“Everyone spoke their mind, and we were all still exactly where we all were when we started, and we had nowhere else to go, nothing else to say. That’s why we came in with the verdicts we did,” Kaatz said.

“It’s tough to convict somebody, especially somebody so likable, with such a positive dream,” he added, noting he voted guilty on the three counts on which the jury could not agree. “[We] respected Elizabeth’s belief in her technology, in her dream. [We thought], ‘She still believes in it, and we still believe she believes in it.'”

Kaatz, a daytime Emmy-award-winning TV writer from Aptos, California, who built a camaraderie with his fellow jurors over the four-month-long trial, often putting puzzles together with them during breaks or watching on as others swapped their turkey, ham, or roast beef sandwiches, said the decision to convict Holmes on four counts hinged on a few key elements.

For one, Holmes bore ultimate responsibility for information disseminated to investors, Kaatz said, noting that the one-time CEO “owned everything.”

“Everything went through her,” he said. “She had final approval.”

The jury also found Holmes’ seven days of testimony to be largely non credible. The 12 members ranked each witness’s testimony one through four, with one being non credible and four being the most credible, Kaatz said.

Holmes scored a two, he told ABC News. A few government witnesses, on the other hand, including former Theranos lab director Adam Rosendorff — who testified that, during the period in which Holmes was raising money from investors, he had apprised her of the dysfunction in the company’s clinical lab — had scored as high as a four. No one scored as low as one.

Kaatz also said that, early on in their deliberations, the jury had decided to acquit Holmes on all four counts of fraud against patients, because the CEO was “one step removed” from the alleged victims, and thus the jury didn’t feel they were directly defrauded.

Although the 12 were mostly confined to the jury box in Davila’s fifth-floor courtroom throughout the trial at Robert F. Peckham Federal Courthouse in San Jose, California, they had a bit more freedom to move around in an adjacent courtroom, where they deliberated.

One juror, who always arrived early, assumed the judge’s chair throughout the discussions. Others took the seats stationed at the two attorney tables. Some chose to sit in a similar jury box to the one they had been seated in during witness testimony, Kaatz said, adding that he claimed a first row seat on an audience bench.

One of the first things the jurors did when they arrived at court on Dec. 20, the day they began their deliberations, was to select a foreman. Kaatz nominated juror No. 2, whom he described as one of the younger members of the group, but nonetheless “very mature and organized.”

“He said, ‘I’m not against it,'” Kaatz told ABC News, adding that the vote for their leader was unanimous.

They then took an anonymous poll to gauge where each one stood on every count leveled against Holmes. The jurors scribbled their first passes at a verdict on scraps of paper and then shared the results. The votes were mixed, Kaatz said.

The 12 then laid out a “timeline of events” on a chalkboard, to which they stuck note papers with “relevant points of evidence.”

Despite their disagreement on some elements of the case, the group got along famously, Kaatz said, adding that he is proud to have worked alongside his peers, many of whom were juggling jobs and family obligations at the same time.

On Tuesday afternoon, a day after his role in the rare takedown of a Silicon Valley CEO ended, Kaatz slumped back in his living room chair.

“It was an honor. It was a duty,” he said. “I did it. I’m done.”