Aerating the soil is a good technique to speed up the process of soil improvement. It doesn’t need to be done every year because the earthworms and microbes will do the job long term.
Some people just like to get their hands dirty. Owning property is a guarantee that you'll get your hands dirty, usually on more than one day during a typical "homeowners" week.
You need to maintain your lawn, including keeping it mown at the proper height, edges trimmed occasionally, and keeping it watered when there's not enough rain.
Besides the natural elements found in the soil, which become depleted over the years, additional sources of nutrients and trace elements need to be added to a lawn's soil to keep a lawn healthy.
Unless a homeowner has a lot of experience at identifying underlying lawn problems, they will need to have a soil analysis made to determine what's in their soil and what's not.
A homeowner has a lot of things to do, especially during the summer months. Hiring out a part of that work makes sense. Hiring a professional lawn care company....well, that's a whole different story
