Pride is very present in Much Ado About Nothing – not because any of the characters suffer from hubris or pridefulness, but mostly because characters are made susceptible when their pride is wounded. Pride is damaged and preyed upon more often than it’s inflated in this play. Both Beatrice and Benedick are inspired to love each other when they’re accused of being too prideful to do so. Claudio and Leonato both suffer wounded pride when Hero is thought to be disloyal, and ultimately Claudio tries to rescue his pride by defaming of Hero. Though pride is not often an explicit motivation or end for any of the characters, it’s a powerful force that influences their actions and feelings.
Claudio chooses to publicly humiliate Hero to restore his pride, which was publicly wounded by her apparent disloyalty.
While none of the characters ever explicitly say that they are acting for their own pride’s sake, all rash actions and over-the-top feelings can be explained by wounded pride.