Michael,
(the writer of this post canot take any respnsibilty for incorect speling until Justin has instaled the spelchecker in the editer!!!!!)
I understand the point you are making, however it may not be substandard.
Paint is applied to the render when the surface is dry, they do this to make the property look good as soon as possible. If the surface is slightly wet it does not matter because the solvent for the acrylic paint is water ie the same as the cement render.
The problem is caused by salts in the render coming to the surface over time this can take place over a few years. I have the same problem over last 5 years in Manilva and in a wall in UK done last year.
The salts make the surface flaky and the paint adhesion is lost. The temperature in Spain goes as low as 3 degrees and can be as high as 50 in direct sunlight and the thermal expansion and contraction causes loss of adhesion.
Settlement cracks occur in most builds, I have the same for first 3 years in Manilva.
On successive repaints the problems normally diminish.