99% of the time there are discussions and an agreement before the transfer takes place. The discussions can be initiated by the player, the coaches at the 4 year school, or an intermediary. Those discussions cover the players reasons for wanting to transfer and what he can expect at the JuCo that will receive him. This is done to determine if it’s a good fit for both parties. When everyone is in agreement that it’s a good fit the transfer is initiated. That’s how it normally works.