A lot of reasons. One, not every program/team depends on deep throws for conversions and TD's. Fromm for example throws A LOT of short passes. Cut's "dink and dunk" with Ainge a few years back would have looked awful in this particular stat. They scored around 40 ppg and their best receiver was Lucas Taylor who if I remember correctly posted a 4.8 40 at the combine. Ainge set a record for completions too.Why is the SEC average so much lower than that then?
That's why I said that was a pretty parsed stat. It means something but only in the context of other stats.