I think it's not easy to be the PM of Singapore. It's impossible to please every Sinkie. That's why Heng Swee Keat dared not to take up this post. Another one who gave up on the Singapore Political scene is Lui Tuck Yew. To me, he was quite a good and responsible minister, but not being appreciated. So, he might as well quit.
Raymond Lim (ex-transport minister) was on the other hand a big fuck and Marlboro Tan was the most bastard of all.