To this point in Luke's Gospel account Jesus has primarily been a teacher to the disciples. Here makes a transition where Jesus adds another role which builds throughout the rest of the earthly mission, sender. There is still much teaching, and teaching will continue as long as people have breath. Still there is a transition to sending the people of the Kingdom into the field as it were.
This is not a subtle or insignificant transition. Jesus seems to know how important it is for a follower to be experiencing the life God has called all of us to rather than just hear about it. The title master teacher was and is given to Jesus. As to his ability to teach others I am not sure there is a parallel. Still no matter how much teaching Jesus offered or how much teaching the disciples sat under, they would not know what it meant to follow Jesus until they went out.
Note the disciples did not complain about not knowing enough. They did not give a list of reasons why they were not fit or able to go on the mission Jesus was sending them. One possible answer to this is that they have it all together. A quick read of the whole of chapter 9 reminds us different. The other explanation is they were works in progress.
Are you simply receiving the teachings and words of God and doing nothing? Jesus is not just a teacher he is a sender. Each and every person is called to go out in mission. This might mean overseas, it might mean across the country, across the street, the driveway or across the room. Nonetheless we are all a send people if we are a people following Jesus Christ.