Really it is a “make or break” for the talent. Do well like Evan Bourne (Matt Sydal), and you are on a roster and out of development. Do not so well like Brayden Walker (Chris Harris) and you get released.
WWE has to weed out it’s development roster. Keeping wrestlers in Tampa for too long just makes it harder to add new blood. So if after a while, and if creative hasn’t asked for someone because of an idea, wrestlers will either just be released or given a chance in the “Superstar Initiative”.
And “chance” can be relative as what the wrestler is allowed to do in the match(es) will depend on what the agents let them do, so a key will be “personality”, and likely that explains the push of guys like Ricky Ortiz (Atlas DaBone), as his “work” has been average at best.