Effective work delegation

In my team from past couple of months I am seeing the current work delegation style does not work that effectively. It's a process fail for us. Though it's a leadership style to delegate the works among team but to make it effective we should choose right people and we himself should know better about the task before delegating same to another person. Choosing a wrong candidate will cost us a lot because the training process will be longer and the work may need continuous review from experts. I am not saying it's a problem with member or it's not good to train them about a task. But if that can be done in a better way then why not choose people those are interested in doing such task. As a leader instead of choosing just a person we should identify the talent. Choosing the right & interested person will continue the momentum and we can satisfy the member as well. More than that before delegation the leader should do that work in person to get to know in depth about the task, so that he/she can give a nice and effective picture to the member, then take feedback from them and more in advance plan for appreciation for same. But my bad we failed to do that..!!