Part of what makes leading ice so hazardous is the fact that, unlike rock, ice melts. For a scary illustration of that point, watch this viral video of a late-season ice climber on Kennedy's Gully (WI5, six pitches) in Ouray, Colorado, narrowly escaping a massive fall when the ice he's perched on collapses beneath him. The only thing that saves the unknown climber is a last-minute top rope thrown to him by a party preparing to rappel above him.
Commenters on the Internet have been quick to blame the climber's poor choice in attempting the route under such warm conditions, noting that the icy smear he's climbing is melting under his crampons. While it's not clear when the video was shot, the ice on much of the route is thin even in optimum weather, and according to San Juan Mountain Guides' website, Kennedy's Gully went out of condition April 25. Still, my guess is that no one has to tell this man what a narrow escape he had. As he says near the end of the video, he definitely owes his rescuers some drinks.