The wait before the first impression
A guest planning a trip rarely looks at a single page. Several tabs are open, a few accommodations are in mind, and patience for any one of them is limited. A page that takes too long to appear loses the guest before the first photo has loaded, and that guest rarely returns to find out what was there. On a phone, on hotel wifi or a train connection, the margin is smaller still.
Speed, in that light, is not a technical detail. It decides whether the visitor is still present at the moment the content arrives. The most carefully chosen photos and the most honest description do nothing for a guest who has already closed the tab.