I’m sad to learn of this tragic news. My thoughts and prayers to his family. He was on a precarious stretch of trail that is narrow, often icy, and with steep dropoffs. The climb to the summit is 15 miles roundtrip with vigorous hiking/climbing. After you get up through the “narrows”, you have to descend back across it while typically fatigued. Unless you know the route is free of snow and ice, you should take crampons with you.
Earlier this year, a group of green berets were training on Longs Peak. They ran into trouble, some of them got altitude sickness, and they had to be rescued by helicopter.
Greeley hiker falls 150 ft. to his death at RMNP – http://www.thedenverchannel.com/news/mountains/greeley-hiker-falls-150-feet-to-this-death-on-longs-peak-in-rocky-mountain-national-park