Why do many handheld landscaping tools use two-stroke gasoline engines?

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Labeled cross-sectional diagram of a V-type gasoline engine for an automobile, showing internal components such as pistons, crankshaft, camshaft, intake and exhaust valves, connecting rods, spark plugs, and intake manifold. — gasoline engine Cross section of a V-type engine.

Handheld landscaping tools often utilize two-stroke gasoline engines because they are capable of producing high power output from a relatively small, lightweight engine design.1

Unlike the four-stroke cycle, which requires two revolutions of the crankshaft to complete a cycle, the two-stroke engine completes its cycle in a single revolution. This is achieved by using the crankcase to compress and pump the fresh fuel mixture into the cylinder, a process that eliminates the need for complex valve trains and allows for a more compact and simpler construction.1

However, these engines have notable drawbacks. They are often criticized for high noise levels and significant air pollution emissions. Additionally, because the design can lead to a loss of fresh fuel mixture through the exhaust ports during the scavenging process, they generally lack the fuel economy of four-stroke engines.1