Small black dots or spots on your legs are just what we call strawberry legs. This gives an overall pitted appearance to the skin that can be unsightly for some people. This usually happens because when you shave or wax, the comedones, or pores are open, and therefore more prone to catching dirt, or trapping oil and bacteria.
In addition, when the follicle is clogged up, or the pore is exposed, air can get inside, which will then oxidize and turn a darker color. Most of the time, strawberry legs can occur because of waxing or shaving improperly. If you shave with dull or old razors, or without any cream, you can cause strawberry legs or ingrown hairs- which can look like strawberry legs.
If your skin is irritated from waxing or shaving, then this can also cause dark spots on your legs. After waxing, your skin can also become clogged up with oil, dead skin cells or other debris, which can also get trapped and cause strawberry legs.
You could be suffering from folliculitis, which is a condition that occurs when the follicle becomes inflamed or infected. This is often caused by bacteria, fungus or yeast entering the skin follicle, which is much easier if you have waxed or shaved recently. After waxing, the skin follicle is more prone to infection as it is open and exposed.
Other people are simply just more prone to strawberry legs. Everyone is different, and some people have larger pores than others, which is completely unavoidable, but you can take steps to prevent it.