Why do you think revolutions occur?

Addressing the sit-in participants by telephone from London's International Secretariat after his release from Southwark police station, MQM chief Altaf Hussain reportedly said a change appeared to be imminent in Pakistan through which the poor will rule the country. According to him, a revolution is the destination of Pakistan in the near future.
Although, the exiled MQM chief appears to be highly optimistic about the arrival or occurrence of a revolution in the country, he needs to study and examine the circumstances that generally lead people to overthrow the existing economic and political structures. In my view, the country has not reached the stage where politicians like Imran Khan and Altaf Hussain can trigger a revolt.