When a building does exterior painting but leaves old, faded or rusty grills as they are, something always feels off. The walls look fresh, but the metalwork drags the overall appearance down.
Doing grills and railings together creates a cohesive look. Fresh black, white or grey paint on metal against newly painted walls makes everything seem updated. From the street and from inside the flat, the view feels more polished.
Also, scaffolding or other access systems are already in place for exterior work, so adding grills into the same project can be more efficient than doing them separately later.