It's to change the government. Any seat you take brings you closer to that goal. WP is 38 seats and 4% away from that. KJ, CSJ and TJS are 44 seats and 14% away. Let's not care what the opposition MP does with the seat.
You want something closer or further? Remember after LTK took over, WP took 10 years to struggle from where KJ, CSJ and TJS was to where it is now.
But Singkies do not want a new govt. They still want PAP in power and WP to stay opposition.