Aside from what others have said, which I think is more important, I would like to point out that most of us don't really like the informally dynastic position of the Kims and might prefer the family retiring to at least lesser roles in politics, all other things being equal. I think most of us would consider it something of a middle ground that there is a trend across the decades of the Kims continuously diffusing the powers of their respective offices to other offices, decentralizing authority, to such an extent that two Kims have technically never held the same top executive position because it was abolished and replaced* at some point between the start of their respective first terms and their respective deaths. I'd expect that last bit to become obsolete eventually but for the general point about diffused authority to persist for some time.
*this is part of the reason that the term "supreme leader," which is an honorific (like "Your Honor," etc.) and not an office, gets used to describe their position.
As a further caveat, all three of them have been at various points General Secretary of the WPK, which is a significant office, but that's not the head of state and there have been long stretches when they were not occupying it (though information on these things is a bit annoying to find).
Aside from what others have said, which I think is more important, I would like to point out that most of us don't really like the informally dynastic position of the Kims and might prefer the family retiring to at least lesser roles in politics, all other things being equal. I think most of us would consider it something of a middle ground that there is a trend across the decades of the Kims continuously diffusing the powers of their respective offices to other offices, decentralizing authority, to such an extent that two Kims have technically never held the same top executive position because it was abolished and replaced* at some point between the start of their respective first terms and their respective deaths. I'd expect that last bit to become obsolete eventually but for the general point about diffused authority to persist for some time.
*this is part of the reason that the term "supreme leader," which is an honorific (like "Your Honor," etc.) and not an office, gets used to describe their position.
As a further caveat, all three of them have been at various points General Secretary of the WPK, which is a significant office, but that's not the head of state and there have been long stretches when they were not occupying it (though information on these things is a bit annoying to find).