Consistency makes a campaign recognisable, not repetitive
Brand consistency comes from preserving the campaign's distinctive design choices wherever audiences encounter it. The lettering on a banner, the image supporting a social post and the website experience all communicate the brand, so each execution needs to feel connected to the same campaign idea.
A unified campaign does not require identical layouts in every channel. Different formats need different treatments, but the underlying design principles should remain stable enough to prevent buyer confusion and protect brand recognition. Without that discipline, individual variations can accumulate until campaign assets no longer look as though they belong to the same organisation. Consistency therefore protects the clarity and force of a distinctive campaign, rather than limiting creative adaptation.
Sources: Why bold design is good business, Creating connections through design