Cutting grass is similar to pruning plants and cutting too much removes the leaf surface where the plant can photosynthesize. If there is not enough leaf surface, your lawn’s root system will weaken as the plant uses up its stored nutrients. Tip. Bare grass patches can damage grass roots. More @Wikipedia
Hover over any link to get a description of the article. Please note that search keywords are sometimes hidden within the full article and don't appear in the description or title.