I don't know the names of all kauravas, but just taking the first two: Duryodhana, and Dushasana: the prefix "Duḥ" is typically used as a negative connotation (e.g. duḥkha [sorrow], durmitra [bad friend / enemy], durāchāra [opposite of established rules]).
Which parent would name their child with a name pointing towards a negative characteristic? Was this a form of "artistic liberty" used to paint the villains in a bad light? If so, what were their real names? Also - why was this literary device used (if it was at all)? For example - Śiśupāla was a villain slain by Krishna, but his name means "protector of children" which seems nice enough - definitely something that a loving parents would name their child.