In these years some manufacturers of airless spray units launched the absurd spot “piston airless is better than diaphragm one”.
Particularly users from Anglo-Saxon countries seem to have absorbed this subliminal leitmotiv: in fact in these countries is quite uncommon to find a diaphragm spray unit, even though they are highly appreciated in continental Europe, former USSR, Arab countries, China, Northern and Southern Africa.
In spite of the evidence, the above mentioned companies convinced millions of users to leave diaphragm airless for piston: in fact diaphragm airless was the real innovation, older users certainly remember it.
Who was not up to develop good diaphragm airless models came back to piston technology and launched a campaign to dissuade users buying diaphragm spray equipment.