8 Washington OK by S.F. supes stands

By John Wildermuth : SFGate – excerpt

…Chiu has been adamant in his opposition to the 3.2-acre development on a triangle of Port of San Francisco land across the Embarcadero from the Ferry Building. He called on board members to stop what could be a costly referendum election and campaign by reversing their approval of a special 136-foot height limit for the project, far taller than the current 84-foot limit along the waterfront.
Both the large number of signatures collected and polls commissioned by opponents of the development show that city voters are against both the individual project and any effort to allow taller buildings along the bay, he said.
“Today we have a chance to vote with a majority of San Franciscans,” Chiu said.
Chiu’s arguments were quickly dismissed by supervisors backing the project, who noted that the 31,000 voters who signed the referendum petitions only heard the opponents’ harangues against the development…
The board’s vote was the final chance to keep the referendum off the ballot. The 8 Washington project will remain on hold, with no physical construction allowed, until after the November 2013 election…  (more)

What motivates the Supervisors to risk their political careers to go against the wishes of their constituents?

Note that President David Chiu and Supervisors David Campos and John Avalos opposed this development.