Tire not sealed on the rim correctly. Worn or poor quality suspension will also cause excessive tire wear, especially cupping. Some accessories when bolted to a motorcycle may cause handling problems. Motorcycle manufacturers have a big job in choosing such things as suspension. They must consider many factors including cost, a soft and comfortable ride, various rider and load weights and a wide range of road conditions.
Cost is a major consideration for manufacturers.
Keeping within budget is mandatory and long term quality and life expectancy of high wear items such as shock absorbers and springs often suffer. Over stressed components such as internal valving parts, oil and springs are generally the first to wear out. To achieve this some cost cutting must occur. Automotive manufacturers have the same problems, however, they offer optional suspension upgrade packages to improve handling, increase load capacity or offer adjustability. These options are expensive, sometimes costing several thousands of dollars but are quite popular because of the improvements they offer in handling stability and load capacity.