In the British system, as I recall, they don’t allow all the juror challenges by the lawyers on both sides. If they need a dozen people for a jury, they call in 14, and pretty much unless you’re related to the defendant, you’re going to be on that jury.
I was always excused from jury duty when I said I had young kids at home. After that, I’ve gone in every time I’ve been called (county and Federal) and never tried to get out of it. Only once did I come anywhere close to being seated. A young woman asked to be excused because she was a minimum-wage hourly employee. Her employer would give her the time off, but she wouldn’t get paid. The trial was expected to run 1-2 weeks. She said she wouldn’t be able to pay her rent if she was on the jury (jury stipends here were $5/day). The judge said no. Who would want that person on the jury - she’d be worrying the whole time about where she was going to live. The prosecutor kicked me out before they questioned her, so I never knew whether or not she ended up serving.