The reader expects fictional characters to have much more "eventful" lives than real people.
I once read that the average real-life policeman fires his gun at a suspect approximately once every 30 years. i.e. most policemen never shoot a criminal in their entire careers, maybe possibly once or twice. But police officers on TV have two or three shootouts with the criminals every episode. The average TV policemen kills dozens or hundreds of people every year. And yet generally the audience accepts it, because we expect fiction to be extreme.
If your heroine is captured by the villains 20 times, this is fine if the reaction of the reader is, "Oh no! She's been captured again! How will she escape this time?" If the story is entertaining, the reader should just accept this. The problem is if the story is getting so boring and or strained that the reader thinks, "Oh, right. She's just been kidnapped AGAIN? Why do her friends even bother trying to rescue her? She's probably used to it by now."
I've read plenty of stories where I think, "Wow, how exciting! The hero defeats an entire army single-handed!!" But I've had others where I think, "Yeah right, I'm supposed to believe that this one guy can defeat an entire army single-handed?" It's all a matter of doing it effectively. And if I had a simple formula for how to make a story engrossing, if I could say, "Just make your sentences this length and use these six words" ... I suppose I'd be a famous novelist and not taking time off work to post on this forum.