What would cause a poor gloss level on new paintwork?

Condensation forming on the surface soon after application can take the gloss of new paintwork. This can be caused by painting in cold, damp conditions or painting outside when rain or frost are imminent. Porous under-surfaces can also absorb gloss and make it appear dull. To remedy, lightly abrade the surface and apply a further finishing coat of paint when conditions more favourable.