#5 The Indianapolis Colts
Believe it or not, Marcus Mariota might not even get a starting spot and could just end being a backup quarterback somewhere else. For example, the Indianapolis Colts took a gamble on former Eagles quarterback Carson Wentz, claim that they hope this ends their revolving door quarterback issue. Whether that ends up being the case or not remains to be seen, but it would make sense for the Colts to sign Mariot as a trusty backup for Wentz
This is just one example of Mariota staying in a backup role, and there are various other scenarios that could play out in that direction.