Poor Generation Problem of Wind Turbines

Why there is poor generation in some of the wind turbines? The reasons could be:-
1. Bad siting.
2. Power Curve related problem ( pitch angle setting and yaw alignment).
3. Equipment Inefficiency.
4.Losses.

To overcome we can
1. Increase the hub hieght.
2.Relocate the wind turbine.
3.Can correct the yaw alignments and pitch settings.
4.Can change the noisy gearbox/generator.