Because grass is the basis of your farming income. If you dont assess your pasture weekly, your farm is losing money.
Inaccurate evaluation is costly too.
Many farmers believe that visual estimation is as good as anything. Unfortunately, assessment of too much pasture is common and explainable by the fact that most of us are optimists. When we assess by eye, unless well trained, those tufts of grass are emphasised in our mental picture. Dry matter content varies dramatically with seasonal change, and without equipment that can ascertain these changes, there will be major flaws in feed allocation. Electronic systems are the only way to reliably assess the amount of your pasture because they measure the dry matter in grass, not the height, which is a particularly important feature.