That's an excellent and very practical question. It's something many urban planners and sustainability officers grapple with. The short answer is yes, making the recycling slot smaller is a common and often effective strategy to prevent misuse, but it's part of a broader solution set.
The primary goal is to prevent non-recyclable items like general trash, food waste, or large objects from being shoved into the recycling stream. A smaller, specifically shaped slot—perhaps only wide enough for cans and bottles—physically discourages people from tossing in a full fast-food bag or coffee cup. This directly reduces contamination, which is a major cost and efficiency problem for recycling facilities.
However, design must be paired with clarity. A tiny slot with a faded, confusing label can frustrate people and lead to litter being left *beside* the bin. The best systems use a multi-pronged approach: a clearly sized and shaped opening matched with bold, simple pictograms showing *exactly* what goes in (e.g., bottles & cans only). Sometimes, a larger, contrasting opening for general waste is placed right next to it.
It's also worth considering other anti-tamper features like hinged flaps or internal baffles that make it harder to reach in and pull items out. Ultimately, the most effective bin design is one that intuitively guides correct behavior through a combination of physical constraint and crystal-clear communication. So, while a smaller slot is a smart tactical move, its success depends on the overall design and educational context.