my raised beds seemed to have lost about 1/3 of their soil. Not sure why. It may be when I weed them some soil always comes with the roots of the weeds, or the soil is settling slowly.
Getting garden soil can be a logistical pain. And expensive. You have to order it and have it delivered, dumped onto your driveway, and then you move it.
BUT, if you own a Ford F150, you just drive down to the gravel yard, pay them $22, and get a huge load of soil.