It depends. While composting does have its place in the waste hierarchy, it isn’t at the top of the list. There is a reason the phrase we all grew up chanting was “Reduce, reuse, recycle!” Looking at the waste hierarchy reduction of materials use and recycling are still at the top, followed by composability, but why?
The reason for this, is due to the fact that recycling can be a more efficient use of energy. For example, while paper products may be compostable, its highest and most proficient use of materials would be through the recycling stream, unless soiled with food waste. When recycled, paper is brought back down to the raw material state to be reused, preserving the energy, carbon and other resources used to develop that paper. If you were to compost that paper, while it would return back to the soil the entire process would need to be started from scratch, resulting in more energy usage.
That isn’t to say that composting doesn’t have its place. Composting is most logical when the likelihood of the material being composted is greater than the likelihood of it being recycled. In instances where the material is prone to be soiled by food, discarded with food scraps, or contaminated and unable to be recycled, composting is the best option.