Osman leaves NSP to join SPP not because he believed in the leadership of Mr Chiam's or Mrs Lina Chiam's leadership.
Jeannette chose SPP, because it makes no difference, especially when one's only ideology is anti-PAP, oppose for the sake of opposing.
the quotes are from here: http://m.todayonline.com/singapore/4-nsp-ex-council-members-resign-hope-join-spp