A good coach is able to analyse correctly the strengths and weaknesses of their team and then act appropriately. Building on the strengths and helping players improve the weaknesses is obviously a key part of being a good coach but it is also about how the coach goes about this.
We know from lots of research that using the ask/delegate style of coaching is where most learning takes place because with this coaching style players are involved in their learning.
A good coach may correct a weakness by presenting the players with the issue to be resolved and then, by asking questions, allow them to come up with a solution. For instance, there may be four possible solutions:
A = the correct and best solution
B = quite a good solution
C = a reasonable solution
D = a solution that works but is quite limited
If the players come up with D, the coach should allow them to try it as the players will give it 100% as it is their solution. Once the players see it is not working so well the coach can again ask questions so they move to C or even B.
The trick of the good coach is to ask the right questions over what may be significant a period of time so the players arrive at the right solution A but consider it their solution and so give it 100%.