TL;DR
The recycler shouldn't be introduced since it forces a cap on productivity bonuses, which go against the very nature of "the factory must grow"There is also another option to fix this
What ?
The recycler (shown in FFF #375) shouldn't be introduced because it necessitates a cap on the amount of productivity any given machine could have.To make sure that there are not tons of useless low-quality items floating about a new machine should be introduced that takes an item of lower quality and attempts to make it higher quality if it fails, it dumps the same quality as the input out.
Why ?
In FFF #376 (the very next FFF after quality) We are introduced to quality research, take that and the boost from max level quality modules and we would very quickly reach the incredibly low cap of 300% productivity, this would stunt the growth of the factory, which is clearly unacceptable. so short of giving each item a custom return value (based on how much productivity was used to make it) there is no other method of removing the cap except through the removal of the recycler.One other option
There is one other optionWe could have the recyclers return less of a percentage of the ingredients from a recipe the further its productivity research is done (each level does 10% so at research level 10 the recycler would return only 12.5% of ingredients (25% base)).
This solution would also allow the removal of the productivity cap as well