The first choice requires terminating one's right of abode in Singapore, not merely leaving. The second choice does not necessarily require a purchase; an employer-provided traditional lifetime pension, or a family-provided lifetime trust fund, generally qualify.
A third choice is never to work (for pay) for an employer in Singapore.
U must be crazy to choose this (in red), see below in red 
All three are perfectly viable choices, available to adults to decide freely.
Q Can I leave CPF LIFE after I have joined?
A Once you have joined or are placed on CPF LIFE, you can only leave the scheme for the following reasons.
You have a medical condition which causes you:
- to be physically or mentally incapacitated from ever continuing in any employment; or
- to have a severely impaired life expectancy; or
- to lack capacity within the meaning of Section 4 of the Mental Capacity Act (MCA) and the lack of capacity is likely to be permanent; or
- to be terminally ill.
You are about to leave / have left Singapore and West Malaysia permanently with no intention of returning for work or to live.
You are a Malaysian citizen and have left Singapore permanently to live in West Malaysia.
You are fully exempted from setting aside the retirement sum in your Retirement Account because you are receiving a monthly pension / annuity payout.
The CPF LIFE Standard Plan, the CPF LIFE Escalating Plan and the CPF LIFE Basic Plan have a refund feature. This means you will receive a refund of the savings used to join CPF LIFE less any monthly payouts you received before leaving. No interest will be refunded. You may not receive a refund if we have paid out all your savings that you used to join CPF LIFE in the form of monthly payouts.
Q Can I be excluded from CPF LIFE if I already have a private annuity or a pension?
A If you are receiving lifelong monthly pension or payouts from your life annuity bought using cash, you may be fully exempted from setting aside the Full Retirement Sum in your Retirement Account and need not join CPF LIFE.
