Cost ($30 for the primary app to each additional school + $50-150 per secondary app) is a concern. Time is also a concern. Most secondary applications have anywhere b/w 0 to 9 essays. I would say that most applicants, especially if they are attending college while applying, can only handle 20-25 applications AT MOST. 7 interviews from 20 applications is a pretty good ratio. 1 acceptance shows that he wasn't very good at interviewing, not that he should've applied to more schools.