It becomes clear as Ulysses sets off on his journey that he feels he leaves Ithaca in capable hands. Ulysses believes that it is in his best interests to leave his son, Telemachus, as the leader of Ithaca when he sets off on his journey: "This is my son, mine own Telemachus,/To whom I leave the sceptre and the isle,—" Ulysses feels that Telemachus will be a good ruler for Ithaca and thus leaves him to rule when he retires.
Tennyson has Ulysses describe him as "well loved" and the father says that his son is capable to "fulfill this labor." Ulysses believes that Telemachus possesses a domestic capacity that enables him to be successful in taking over for him as the day to day ruler of Ithaca:
Most blameless is he, centred in the sphere
Of common duties, decent not to fail
In offices of tenderness
The idea of being focused on "common duties" and Telemachus's disposition as being described as "decent" enable him to carry on ruling over Ithaca while Ulysses sets out on his voyage of retirement. Finally, Ulysses believes that this is a natural order or progression that must be embraced: "When I am gone. He works his work, I mine." This becomes a critical point in the poem in that Ulysses feels that Telemachus must fulfill his duty as taking over for his father while his father tends to his own notion of "work" that will be evident in his departure from Ithaca. It is in this light where it is clear that Telemachus will rule over the island when Ulysses retires.