Just recently, I’ve had the chance to witness how a team really hurt losing valuable time even though everybody was highly motivated and executing their tasks quite efficiently. The situation revealed a distressing common issue with delegating: managers thinking things half through and then delegating tasks taken out of context.

There are two challenges here: first, managers identifying a problem already start resolving it in their minds. Then they delegate tasks to their team without providing proper background and the already (in their minds) existing first half of the solution. 
That gap often is not recognizable for the team, since the tasks they are handed on are consistent – only not directly related to the original problem. Eventually they will figure this out, and after some frustration and unnecessary additional time and effort, everything will finally work out. On top, the manager erodes his reputation with stunts like this.

How can we do it better? Delegate objectives rather than tasks. Set clear expectations as to what benefits accomplishing the objective brings about, and how you will measure these benefits. Tell them what to achieve and not how to do it. They'll figure out the rest on their own.