As mentioned in an earlier article (“Committed” to a Problem: How to Fix College Football Recruiting), high schools teenagers have a difficult time deciding which school they want to spend their next four years.
Putting in an early signing period would just create potential scenarios where a kid commits to a school, only to later find out that he prefers a different school, often for reasons out of his control such as coaching changes, scheduling conflicts for visits, or changes in a family situation.
And if he had already signed with that school, getting out of the commitment would not be that easy. As of right now, recruits are given until National Signing Day in February to try to make the absolute best decision, and keeping only the one later signing day helps eliminate the chances of them making a mistake on it.
On the flipside, coaches need the extra time to be sure that they are bringing in the kind of student that their school desires. An early signing period would probably occur before first semester grades are finalized, leaving a gamble on the status of the student entering their final semester or enrolling early in college.
There certainly are issues that it would fix, such as the constant commitments and de-commitments, but ultimately an early signing period would make some aspects of recruiting better and some aspect worse, and if that’s the case, it might as well not be instituted.