That's an excellent question that gets to the heart of practical public space management. There isn't a single "better" option that fits every plaza, park, or transit station. The ideal choice depends on a balance of factors including user behavior, maintenance capacity, and space aesthetics.
A single, large centralized bin can be more cost-effective to install and, in theory, easier for collection crews to service at one point. It might work well in a highly controlled setting with predictable, high-volume waste generation. However, the main drawback is user convenience. People are less likely to walk out of their way to dispose of litter. This can lead to trash accumulating around the single bin or being left on benches and the ground, defeating its purpose.
Several smaller, strategically placed bins often promote a cleaner environment. By placing them near natural gathering points—benches, food vendor areas, building entrances, and along common pathways—you make disposal the easiest option. This "convenience factor" is crucial for encouraging public compliance. It also spreads the waste load, so if one bin fills up, others are still available, preventing overflow issues.
Consider maintenance, though. Multiple bins require more frequent collection rounds and higher labor costs. For a space with limited upkeep resources, a few well-placed larger bins might be more sustainable than many small ones that overflow quickly.
The best solution is often a hybrid approach. Use several medium-capacity bins in high-traffic zones to capture waste at the source, complemented by a larger central bin for peak times or bulkier items. The key is observing how people use the space. Watch where litter naturally accumulates—that's where you need a bin, regardless of its size. Ultimately, the goal is to make the right action (disposing of waste properly) the easiest one for the public.