asynchronous growth cycles

Modern marriages are based on the idea of mutual promotion of personal growth and what breaks them the most is the emergence of a major asynchrony among the growth cycles of the partners.

When one partner experiences an exponential growth in a certain area, he or she falsely believes that this will go on forever. But exponential growths never continue forever. Compared to linear growths, they are more thrilling, correct, but they are also more short-lived. 

This is the reason why traditional marriages are based on vows like "I promise to be true to you in good times and in bad, in sickness and in health. I will love and honour you all the days of my life."

Stasis may always be around the corner. You never know.