According to Osho, the secret is that he does not work at all: he is simply present and available. Transformation happens when two availabilities meet, like a seed meeting soil, so nothing needs to be done. Because it is love, not labor, he never tires; one presence can nourish many if they are truly here and open.
He helps many people at once by just being like open soil; if you show up fully, you grow on your own.