Passage: The Everest Base Camp trek on the south side is one of the most popular trekking routes in the Himalayas and is visited by thousands of trekkers each year. Trekkers usually fly from Kathmandu to Lukla to save time and energy before beginning the trek to this base camp.  However, trekking to Lukla is possible. There are no roads from Kathmandu to Lukla and as a result, the only method of transporting large and heavy goods is by plane.

Question: Why would the trekkers want to fly to Lukla from Kathmandu?
to save time and energy