Well, lets see.. Backup QB #1 in year 1, Tristan Gebbia bolted as soon as he lost the starting job leaving the team in a lurch and without a backup QB. Noah Vedral was brought in as a transfer, but the NCAA jacked around and didn't approve his eligibility until late in the year. No transfer QB was pursued then because we had Martinez and Vedral.
Backup QB #2 Noah Vedral decided to transfer after the 2019 season after being beaten out for #1 and questions as to whether he had been beaten out for #3 by McCaffery. No transfer was brought in because we had both Martinez and McCaffery who Frost thought were pretty equal in talent (at least he claimed).
Backup #3 Luke McCaffery bolted after being handed the reins, given every opportunity to win the job and failed. Frost coddled him as much as humanly possible to get him to stay too, didn't work. - I fully believe he's the future at QB, We have co- #1's at qb. blah blah.
Backup # is now Logan Smothers. A redshirt freshman who still has 4 years of eligibility. One could argue Frost should have brought in a graduate transfer to serve as a one year backup- but why waste time and energy coaching another backup who is just going to transfer and not do the program any good in the long run anyway.
Frost also probably wanted to avoid dividing the locker room as we had heard rumors of with McCaffery, believing team unity and a serviceable redshirt freshman backup was an even trade. This way the QB who actually wants to be here long term gets the #2 reps in practice and you're building him for the future rather than to have him transfer to another team.
That's how you end up where we are at QB. You get burned by three consecutive #2 qb's and decide coaching up the next long term solution is better than wasting time and resources on someone else who will likely burn you when they don't win the #1 spot. - Even if the next long term solution isn't fully ready to be "the guy," now.