Swiatek wants to play for Poland, but the current calendar makes it pretty tough for her to do so. She spoke about it in the past, even going as far as to hold talks with the governing bodies to find a solution.
Unfortunately, the bodies are steadfast in the way they want to run things, and it doesn't suit the Polish superstar. She played at the WTA Finals this year winning the event but the Billie Jean King Cup started literally the day after.
Playing so soon after a gruelling week makes very little sense and risks injury, which is why she didn't. It's a source of great frustration for her because she wants to play but has to make smart choices that won't leave lasting effects on her career.
I regret it and would like to play in the Billie Jean King Cup finals, but such a decision could have negative consequences. If I had performed there, I would probably be suffering from an injury or a lot of fatigue and would not be able to start training early enough to prepare for the performances in Australia.
Speaking further to Rzeczpospolita, Swiatek confirmed that playing for Poland is the greatest honor for her, it's just hard to do with the way things currently are.
Playing for the country is the greatest privilege, but I try to represent Poland in various ways, not only during such tournaments, but also by showing good play on other world courts. I don't want to compete when I can't give 100 percent. I'm not prepared to step onto the court and win. The situation is more complicated than people think.