The lovable rogue is generally regarded as handsome or attractive and his daredevil attitude further makes him sexually desirable to other characters.
Lovable rogues are not the standard paragons of virtue because they frequently break the law or seem to act for their own personal profit; however, they are charming or sympathetic enough to convince the audience to root for them.
As with the case of George Wickham in Pride and Prejudice, authors may even intentionally write them that way in order to hide the fact that they are a villain from readers until this information becomes necessary to plot.
[1] Although they appear at first to act only for personal gain or to break the law needlessly, lovable rogues are often justified in these actions later on due to some ethical motivation that had not yet been revealed at the time or, at least, have the capacity to atone for their wrongdoings.
Despite his common external appearance of selfishness, foolhardiness, or emotional detachment, the lovable rogue may in fact strongly associate with a highly idealistic belief system and understand the concept of a code of honor so highly valued that it transcends normal social constraints such as conformity, tradition, or the law.