Attrition rate is actually better than what it was from 05 to around 2010.Valve trains take a beating andcooling systems are the biggest culprits.Perfect example. First year(2005) Carl Scott won Unlimited and was running low 8s.It took til 2010 for someone to run in the 6s.Thats a big drop in E.T.Driver fatigue can lead to over looking things that come back to bite you in the but and cause you not to finish.Lets say you leave a track late and break down at 1 a.m in the middle of no where.No parts store open etc and you are 200 miles from the next track.Staging lanes close at two pm.You have to find a way to get parts in the morning,fix your car and still have to drive that 200 miles before staging lanes close.Guy I crewed with in 2010 we broke a fuel injector on the way to Indy.It was an odd one that Oreallys didnt carry.Another competitor came by at 2 AM in the middle of no where and gave us a ride.The next morning we found a place in Indy on Gasoline Alley that got us an injector.Fellow racer hauled back to Indy so he could get a pass in.While installing the bad injector we found a few other minor things we had to address to make it to Indy.Git it fixed and hauled to Indy and hoping to be in the lanes before 2 PM.We get there at 1:50.Dont recall the reason but HotRod changed the cutoff time to 1:30.We got a DNF.