I think the sweet spot is: visible enough that you notice one without looking for it, but not so loud that the street feels like a bin showroom. In practice, that usually means a bin should be easy to spot from the main walking line—maybe 10 to 15 meters away—and clearly readable as a bin at a glance. If I have to hunt for it behind a planter or around a corner, I’ll probably just keep the wrapper in my hand or, worse, leave it somewhere.
Placement matters as much as design. Put bins where people naturally pause or finish something: near crossings, bus stops, cafe exits, park paths, and queuing areas. Use contrast—color, shape, or a simple icon—so they stand out against pavement and walls, but avoid flashing signs or giant slogans unless the area really needs them. A clear opening and a visible aperture help too; people should understand where the waste goes without touching anything gross.
Lighting is underrated. A bin that looks fine at noon can disappear at night. Good street lighting, reflective details, or a light-colored lid can keep it usable after dark. And don’t hide bins to make a street look tidy—hidden bins don’t get used. At the same time, too many bins in a row can create visual clutter and make people ignore them.
So my rule of thumb: make bins obvious along the pedestrian’s path, readable at a glance, and placed at decision points. Visible, not dominant. If people can see it, understand it, and reach it without a detour, they’re much more likely to use it.