Cost-benefit analysis is a weighing-scale approach to making business decisions: all the pluses (the benefits) are put on one side of the balance and all the minuses (the costs) are put on the other. Whichever weighs the heavier wins.
However, since the story constantly points out Jon's conflict with his illegitimacy and Ned's strict code of honor, many fans have come up with a theory that actually explains who they think Jon's parents really are. Fans know the theory as R+L=J.. R+L=J would refer to Jon Snow (J) being the child of Rhaegar Targaryen (R) and Ned Stark's sister, Lyanna Stark (L) rather than Jon being the illegitimate child of Ned.
Casting rumors suggest Game of Thrones could potentially flashback to a scene revealing Jon's parentage, and Sean Bean has said he believes at some point he will return to the show in flashback form to show for that scene.t's inevitable Jon's true parentage will be revealed in the books, as the showrunners have often told a story about how when they first met Martin, he asked them who Jon Snow's mother was, and they jokingly credit that their answer helped convince Martin he should let them adapt his series.