When it comes to Japanese style cloth diapers, what nubmer of inserts makes it thin, average, thick, and really thick?

I’m asking this for a story I’m writing and I have absolutely zero experience with the topic, so any knowledge woul be appreciated. Thanks for reading this.

I think they’re designed to work with a single insert, change regularly. So even two would be ‘really thick’ and more than that would be ‘the cover doesn’t fit properly and won’t work any more’.