Why does a climber need good agility?

As a budding young climber myself I can see why being agile helps you climb a lot better.

Being agile for climbing is great. You can reach higher grips to make your climbing faster and more efficient. This is good because you won't have to strain to grab any grips, meaning you can develop your climbing strategies quicker. Moving quickly and lightly on climbing wall is good so you can move on to harder walls.