Hello JDC2071.
Thank you for sharing your experience. The maximum runtime often applies to a flat, open yard. Slopes and obstacles require more power, and users can expect running time to be less, if this is the case. Runtime measurements are also related to the condition of the grass and if it is well-maintained. Tall, thick grass requires more power, and you must mow it slower, consuming added runtime. Here are a few tips to ensure the max runtime is achieved. Ensure you charge the battery fully before each use, maintain the battery properly by cleaning terminals, avoid extreme temperatures during storage, consider buying a second battery for larger lawns, mow in a straight line, and choose a mower with a powerful battery suitable for your lawn size. If the grass has been left to exceed 4 inches, we advise that you raise the cutting height and cut no more than one-third of the length of grass at a time, wait a couple of days and do another one-third, cut when grass is dry and walk at steady pace to allow the blade to work more efficiently. As the lawn becomes consistently maintained you will see the cut and runtime improve. We hope others will find your review helpful. If you ever have specific questions or concerns about our products, contact Greenworks via Live chat on our website (www.greenworkstools.com), call us at 1-888-909-6757 (1-888-90WORKS) or refer to the FAQ ask section of the tool or ask us a question, anytime.