Clearly you are using an inferior low-flush toilet. I have a 1.2 gallon model (American Standard Champion 4) that has never once failed to work in a single flus

Clearly you are using an inferior low-flush toilet. I have a 1.2 gallon model (American Standard Champion 4) that has never once failed to work in a single flush, and a _lot_ of toilets fail me. Including the monstrously high-volume ones they have in the British Isles.