Why revolution hasn’t happened yet?

The fundamental law of revolution, which has been confirmed by all revolutions, and particularly by all three Russian revolutions in the twentieth century, is as follows: it is not enough for revolution that the exploited and oppressed masses should understand the impossibility of living in the old way and demand changes; it is essential for revolution that the exploiters should not be able to live and rule in the old way. Only when the ‘lower classes’ do not want the old way, and when the ‘upper classes’ cannot carry on in the old way—only then can revolution triumph. This truth may be expressed in other words: revolution is impossible without a nation-wide crisis (affecting both the exploited and the exploiters).

V. Lenin - “Left-Wing” Communism