If a portion of that meristem has cells lacking the ability to make chlorophyll, then all cells derived from and above those cells will have the same defect. Variegated leaves are freaks, but they are truly freaks of nature. Especially in the tropics one can find species with variegated leaves. Horticulturists brought these species into cultivation , and in greenhouses and nurseries people have also searched through their stocks for spontaneous mutants. Because white patches on leaves are not photosynthetic, we should not expect nor do we find that variegated forms grow as vigorously as do nonvariegated forms under identical conditions.
Variegated forms are also sensitive to damage by intense sunlight.
This explains much about how these plants are used in landscaping. They grow more slowly and hence may be less prone to grow too large for a space. They not only do well in shade but also benefit by being there, whereas fully green plant forms may not be happy and may require more sunlight. See now why variegated forms are used as accents with green-leaved plants in shady gardens. The presence of light areas on leaves tends to brighten a shaded area of the garden or dark corner indoors.