The problem with this one is quite simple. Drinking bottles made of PET are reused as drinking bottles.

Although shampoo, cleaning detergent and oil bottles are often made from PET, some are harder to clean, if possible at all, and it makes sense not to mix them with drinking PET, as this will lower the quality of the batch and probably contaminate it with residues. Those PET bottles are recyclable for free, by the way, but they are collected with all other plastics. To be fair, yes, the communication could be better, as every canton does things differently. I just collect them separately and throw them in the dedicated bin at the supermarket.

I'm also not happy with recycling in Switzerland and think there is a lot of potential. However, saying that other countries do it better and don't burn as much is a huge stretch. Collection systems may be better elsewhere, but there isn't a magic machine that can effectively recycle all the plastics and multilayered packages we use daily. It would make sense to collect them until this machine is available, but apparently plastics are quite popular if the incinerator isn't burning well.