>>49424927If you mean the pokeballs that miss a pokemon and land in the grass, they just land in the grass. Since most areas in regions are protected by pokemon rangers it's hard to urbanize things like thick forests, so when your pokeball disappears into the foliage it doesn't make too much sense to spend hours searching for it, pokeballs are cheap and affordable so most trainers tend to just leave them lying around. Now this isn't to say that they end up just rusting where you lost them, there are environmentalists and workers who go and clean areas daily to collect all the missed pokeballs and other garbage laying around, most pokemarts will buy these discarded balls back for a fraction of the price and resell them to make a profit as well! If you're really strapped for cash head on out to the wilderness and start collecting pokeballs left by trainers, think of it as collecting cans.
I can't really explain how pokeballs work myself, I study pokemon, I'm not an engineer. I apologize for not being as knowledgeable on the subject as you may have hoped, but you can always take a tour of a pokeball factory and learn from the workers there!