Depending on the time a business has been around, buying new things at the start of the business does not always work out. If you happened to buy used office furniture in order to get the business going, then you may find that some things are starting to fall apart. If this happens with the office chairs, then the bests steps are to determine whether you are able to fix chair without buying anything. However, if that is not going to work, then usually most find that replacement office chair casters fixes the problem.
Every once and in a while, someone should go around and inspect all wheeled chairs for anything that could lead to someone getting hurt. Keeping up with inspecting things for defects can potentially add up to big savings for the company. This is also important for employee safety and avoiding accusations of negligence in case of chair related injuries.