Aeration reduces compacted soil. Compacted soil doesn’t allow the grass roots to develop deep into your soil, and we all know the importance of your roots running deep. Deep roots increase drought and disease resistance. Compacted soil can also help develop a thatch layer too. Aerating your lawn breaks down the thatch layer and allows your grass to breath.
Aeration also increases lawn density by allowing new grass plants to begin growing. Lawn density is a huge factor in your lawn fighting off the hot Valley summers. The denser your lawn is the better it shades the soil so that it does not dry out too quickly.
Probably the most important benefit of aeration is that it allows oxygen, water, and nutrients to get deep down into your soil where it belongs.
ATLM only does core aeration which removes a core of soil and turf from the ground and places it on the surface of the grass. It is best to leave these cores and let them break down to put nutrients back into the soil as they typically break down in two weeks or less. Some companies aerate with tines that poke holes in the ground. This can have a negative effect and actually create more compaction because you are not removing plugs of soil but you are smashing the soil together in order to create a hole in the ground.