The 34-year-old's decision to leave the show came as a shock to fans, considering she'd only starred in the title role for one season.
Addressing her exit on SiriusXM's "The Jess Cagle Show", however, Ruby denied that a back injury was her main reason for her departure, insisting having time to think about her acting career during lockdown influenced her decision.
"I think what played a bigger part was more, we got shut down early. We didn't get to finish the first season, which is such a shame, especially for a first season show," she explained.
"Then we went into lockdown with Covid and thinking of in quarantine and locked down, there was a lot of thought and reflection and everyone did it. You know, we all kind of thought about where we're at. We were discussing the show and we had a conversation."
She continued, "I had a great time on Batwoman. I am so proud of what we achieved. We set out to achieve something pretty significant, the first-ever live-action Batwoman and the first-ever out gay superhero, her and Kate Kane."
"I love that character and the whole experience, but we did have a discussion and we sort of mutually agreed that probably what was best for the show at the time was they go in a different direction and I go in a different direction."
Ruby also insisted that she doesn't have any bad feelings about her exit and will be watching the second season, which will star Javicia Leslie in the title role.
"It was tough cause it was sad cause we will love each other, but also it made sense for so many different reasons. And I think at the end of the day, I'm really excited to watch season two. I think the show is great. I love the cast," she smiled.
"I'm still in contact with everyone, but it was a decision that we talked about, we discussed, we slept on. But at the time with all that reflection, it just seemed like the right thing to do."