If it's recycling or trash it should always be a common color. I'm used to blue for recycling but we should all agree on a single color. Green to me has always been common trash. Also I hate how recycling isn't standard. I know reasons why they aren't but I wish we'd all come together as a country to fix that (among the other 5,000 things).
A common color would maybe help, but the bigger problem is recycling is still a mess of different companies on taking certain things. Plastic is especially problematic. Sometimes cardboard is separate, sometimes it's all paper, others don't take glass, some want lids on jars, some no lids, if you want something exotic like Styrofoam or batteries then go fuck yourself. And then there's electronics...
Friend of mine at her apartment complex, finally got a recycling dumpster. It didn't last long as the vast majority of people didn't care and just thought to use it as a second garbage dumpster. The idea of spending even a little time sorting out recyclables was too much for that place so they ended up losing the option to recycle (locally at least). She was furious with people.
I always wondered what happens in the facility where they get "illegal" items, do they just dump the batch in the common trash? Do they have people separating what is good from what is not? And if they have people separating, does it matter if people follow the recyling guidelines?
Once worked for a municipality when the contracted garbage collectors complained that there was too much recycling in the trash and the other way around. They essentially have to trash everything in the recycling if it's contaminated.
We had to do some public information campaigns to try reduce it or the company would raise their rates, which would affect tax payers. The message did seem to get across to people, as the company stopped complaining.
It could be in large red flashing neon and people will still ignore instructions like this.
Even if the trash dumpster is a mere 50 feet away.
People just don't care. Once it's out of their hands, no matter where it ends up, it's someone else's problem.
One complex where I used to live, our trash dumpster was a full on compactor, very nicely concealed behind a small hill. Signs leading up would say, "No cardboard!" Signs plastered all over the machine, "No cardboard!"
Yet, at least once, if not twice a week, the thing would be clogged because people would toss in boxes by the truckload. Not even broken down.
Meanwhile, just around the corner, a specific dumpster meant for cardboard only that would take all of 10 more seconds to get to.
I swear all a city would have to do is put "HEY, IF YOU PUT DISALLOWED STUFF IN HERE, THE WHOLE ENTIRE TRUCKLOAD IS REJECTED BY SOME GUY MAKING MINIMUM WAGE AND ENDS UP IN THE LANDFILL thank you please pay your parking tickets too <3 - City" and at least some more people would make better or less-lazy choices.
I wish our recycling dumpsters had more specific signage than just no trash. I have printed out the rules from the trash companies website and hung them near the dumpster and my condo association pulled them down. Pretty sure almost all our recycling gets diverted to trash due to contamination.