A salad bowl sociologically has come to imply a cultural homogeneity you see in places like the USA, highlighting the most important charachetristic of a good salad. The ability to retain your individual flavour while mixing in seamlessly. Making the whole more than a sum of its parts. And like dressing and fresh produce, the salad bowl does that for you.

There are 7-S's of the Salad Bowl.
Shape: It looks and feels like a salad bowl should. The perfection in the roundness of a salad bowl is a quality that is of concern only to the woodturner. The greater majority of the folks who are buying a wooden salad bowl will know that it is wood, and that wood will warp and move. Perfect roundness is not a factor in their purchase when the "Seven S's" are satisfied.
Size: It fits the salad being served, neither too small or too large. The volume of the bowl should match the amount of salad being served. It should neither be overflowing with lettuce nor appear to be empty. The "perfect" Salad Bowl is 12" diameter. Less than 10" is too small. Larger than 14" is too big for most folks. Within this range, the volume of the bowl is determined by its depth.
Solid: NO soft or porous wood, no voids, no holes, no knots, and no patches. Trapped food particles equate to germs, period.
Smooth: It is easily cleaned. There are no frills, no carving, no beads. Keep it simple. The inside of the bowl must be a smooth form that is easily cleaned. This means that there can be no sharp corners, beads, grooves, or carving on the INSIDE of the salad bowl or on the rim.
Stable: It stays in place on a table or countertop, not easily tipped over. This one is simple; like an obedient dog, the salad bowl must SIT and STAY where it is placed.
Sight: A salad looks good in it. It is appealing and appetizing.
Smell: It has either a pleasant odor or none at all. Lying unused in a cupboard should also not give it an unpleasant odour. Or any odour at all.