The soil in these beds will be close to perfect, since you will make it. Gardeners naturally want good soil, but if it doesn't drain, you may as well forget about planting vegetables. It is drainage that takes those dreaded salts down with the water. The added organic matter also warms the soil so you can plant sooner and hasten vegetable maturity. The organic matter will also cool the soil as the weather heats up to make the vegetables sweeter and tastier.
People are basically clean and tidy, preferring to keep a defined area neat and free from litter.
This psychology seems to come into play when you raise the bed. You become more meticulous when caring for the garden. In fact, you'll pounce on invading pests as soon as they arrive. I guess it is because you are physically closer to the plants and see problems before they become major ones. Small hand tools will more than do the job as you'll do most of the work sitting on the edge of the bed.