New things get planted, grow, run out of space, move to new space, and the cycle repeats itself. This is what is exciting about cities. People can move around, according to life requirements. A single person can start in a small apartment, move to a larger one, or even a house, after marriage. With children, larger space may be needed.
Alternatives are readily available.
Similarly, a business might start small in one district, expand to another with growth, and yet another with more growth, and, perhaps, leave town with maturity and expansion. In a healthy city, businesses move and leave town, but new, emerging businesses take their place. Variety of opportunity the variety within the garden nurtures the new. This variety gives the city, the community, the neighborhood, its strength. Understanding this, Urban Husbanders in the 1970s fought the demolition in Brooklyn of the tightly knit Northside neighborhood of small homes, local businesses, and scattered factories for the excessive expansion of one company and assisted that community in strengthening the resources already in place.