Is it a good idea to replace the policy with another policy with better returns?

It depends on the situation. If you are an insurance policyholder and it is not long after you have bought the policy, you can replace the policy with another policy if you see better returns. But if you have purchased that policy long ago and already paid many premiums, then it is not advisable as you will lose all the benefits of the previous policy. Also, the premium will go high as you grow older. Another issue you will see in this case is that the two-year contestability period will also begin again.