In the final episode of the original run of Samurai Jack, Jack faced off against The Guardian, a powerful man guarding one of the last time portals from all but anyone capable of defeating him.
The Guardian had insight into Jack's future, stating after Jack left that he would eventually try again and succeed -- but it wasn't yet time. We are then shown Future Jack.
However, in the revival season,
Jack returns to the site of the battle and finds the portal closed, with guardian's broken glasses on the ground. Jack then has to create a new way to get back home, as all the time portals have been closed. This also stops his aging process, which further goes contrary to the visions shown in the former-finale.
Has Genndy Tartakovsky stated why this change in plot course was made?