Causes When coating the surface on which tiny holes exist, those holes are exaggerated once the flash time is over as the air inside those holes will naturally float. Other causes include using low-quality paint and neglect to prepare the surface with primer. High viscosity or improper water dissolving also tends to cause pinholes. Coating old surface with pinholes without proper fixing is definitely causing pinholes or ant’s eyes on final finish.
Solution Coating the affected area without proper fixing can exaggerate the holes once the flash time is over. Better fix the pinhole with wall putty all over the surface, leave dry, sand with sanding paper, prepare the surface with primer and refinish.