Our compost is usually too dry usually, not turned enough and we ignore the guideline of the correct ratio of 2:1 brown to green material. They are the three key points. Though over the years our soil has greatly improved, and being mostly a native garden, the vast majority of plants are happy with what they have. Our vegetable garden does need more help. We are going to buy a heap of mushroom compost. Some good composting advice can be found here.