Some effects trigger when you enter capital locations For example, The Parthian’s Dress for War Prowess says: “When your encampment moves to a Capital location, The Parthian fully heals.”
These effects only trigger when movement is ended in Capital locations. They can be taken even you choose to spectate at the Capital instead of fight (though in the example of The Parthian above, this has no additional effect as your hero already gets to heal with spectating).