After Britain returned Hong Kong to China in 1997 it has always demanded more freedom than any other part of the country. This was recognised before the hand over and china adopted a One Country, Two System policy, and anointed Hong Kong S.A.R status - a Special Administrative Region.
It was hoped that Hong Kong would be able to elect it's new Chief Exec by universal suffrage, but due to disagreements with the Electoral Reform Proposal* from China the peoples representatives(Legco) voted against this.
The democrats seem to be hell bent on disagreeing with China at any opportunity in the short term rather than considering the long term needs of the Hong Kong people. Like teenagers rebelling against their parents. By rejecting the proposal in 2015 it means that I cannot vote in the 2017 Chief Executive elections. The democrats want any citizen in Hong Kong to be able to run for the post of Chief Executive. In fact they gave an all or nothing demand, and the people of Hong kong ended up with nothing. The ability to vote must be taken, grabbed, snatched, devoured any time it is offered. It is our proof that we have a democratically elected government and we can protest as a democracy.
*Elctorial Reform Prosal: https://en.wikipedia.org/wiki/2014–15_Hong_Kong_electoral_reform