Here are some of the widespread issues with plastic recycling, some well-known, others less so:

- The recycling process produces microplastics that end up in the environment

- That's because most plastic recycling processes require large amounts of water to clean the plastics; the only exception I know of is "dry-pressing", but that's useless for packaging, which is one of the biggest contributors to plastic waste

- Each recycling 'pass' reduces the polymer chain length, thereby making the plastic weaker, meaning it can only be recycled a finite amount of times

- 'Virgin' plastic (ie. produced from raw oil) is cheaper than recycled plastic to produce

- In some countries, the definition of "recycling" includes "burning it for power"

- A major bottleneck in the recycling process is the plastic type sorting stage; these machines are expensive and have limited capacity

- While soluble and metallic contaminants can often be automatically removed, others (such as fabrics) cannot, and require humans to pick it out

- Most sorting processes are optical, and just straight-up cannot sort black plastics because they cannot 'see' what type it is; all light is absorbed

- Sorting by plastic type is a hard requirement; not doing so means you will end up with uselessly weak plastics after recycling

- Only packaging plastics can be recycled in most recycling streams; non-packaging plastics typically have additives that interfere with the recycling process, or aren't even food-safe

- Plastic 'film' is notoriously difficult to recycle into anything useful; we're not just talking saran wrap here, but also for example plastic bags and the shrinkwrap around drinks bottles or cans! Basically anything you can fold without breaking it.

- Composite plastics (ie. things made from more than one plastic type) are essentially just unrecyclable; this often includes things like 'plastic tubs with aluminium lids glued to them'

- Did I mention that virgin plastic is cheaper? Plastic that's collected for "recycling", if not burned locally, is often just shipped to poorer countries to get rid of it, typically with large amounts of contaminants

So yeah, about that 'recycling'...