Why does this code fail to display text on the OLED?

Why does this code fail to display text on the OLED?

from PIL import Image, ImageDraw
from luma.oled.device import ssd1306
from luma.core.interface.serial import i2c

serial = i2c(port=1, address=0x3C)
device = ssd1306(serial)

image = Image.new('1', (device.width, device.height))
draw = ImageDraw.Draw(image)
draw.text((0, 0), 'Hello', fill=255)
# Missing device.display(image) call