The sugars, carbon and nitrogen are mainly used to form amino acids. Phosphorus to form enzymes, sulfur is important in forming thio-aminoacids, calcium for pH control and cell walls, molybdenum and cobalt for fixation of nitrogen from the air. All of the substances must be in a form that the microbes can use, or the conversion of elements to useable forms can take years, causing a slowdown in the soil life. Planters II works now to supply nutrients to plant and microbes alike. Every time you take an ear of corn, a pod of peas or pick a flower, minerals are removed.
Regular fertilizer supplies little or none of the needed minerals.
Compost is good but since little minerals remain in the stocks of plants, compost will not supply necessary minerals. Manure is only as good as the feed that the animal ate, if the feed is poor in minerals then the manure will be deficient.