The answer to 'why is my sprinkler system thin grass' is that there are several common causes, including improper sprinkler head placement, inadequate water coverage, or soil compaction. Thin or patchy grass around sprinkler heads can be a sign that the system is not providing enough water to that area.
Some of the most common causes are sprinkler heads that are blocked or obstructed, leading to uneven water distribution. Soil compaction can also prevent water from properly soaking into the ground. Additionally, if the sprinklers are not adjusted correctly, they may be missing certain areas of the lawn, leaving the grass thin and dry.