By far the most effective mulching mowers are those that are dedicated machines with no other function than to mulch grass clippings. Single purpose mulching mowers are designed with domed cutting decks that produce maximum under-deck airflow, and grass clippings are held and tossed around repeatedly to meet the specially shaped blade surface as many times as possible. This process creates the most rapid decomposition of the clippings and the best results for your lawn. Single purpose mulching mowers are also the simplest machines to use with no unnecessary attachments or grass collectors to hinder performance or manoeuvrability. Gardeners requiring more flexibility than single purpose mulching mowers have to offer may wish to consider a 3-in-1 or 4-in-1 machine, however the additional features tend to come at the price of performance.