Ng Eng Hen and Mah Bow Tan not voted into the PAP CEC?

It has been reported that Ng Eng Hen and Mah Bow Tan were both not elected into the new PAP CEC. What are the implications of their absence as both are heavy weights. Both have chalked up great works especially in the use of CPF money. Eng Hen came out with the compulsory CPF Life scheme which helps the CPF account holders to buy compulsory insurance for their retirement. Mah Bow Tan helped HDB flat owners to buy more expensive HDB flats at market price with subsidies. Both are great schemes and have been very well received. The success of the above two schemes cannot be the reason for their non election into the CEC. What else could be the cause or causes? There should be no problems with their leadership, as both are giants in their own rights. Eng Hen is perhaps the most macho and charismatic of the current PAP leaders. Mah Bow Tan even has his own column in the media to explain how great the HDB and housing prices were, and his familiar face is a already a household name. The only gut feel I have is that both may want to quit politics. Who knows, both may not run in the next GE. It will be a big loss of two super talents. But their talents will definitely be put to good use outside the govt. They will have ample opportunities to apply their great policies and formula in the private sector. They could take the same route as Chee Onn or Boon Yang and live happily ever after.