If you are trying to work out what the best strategy is for having an income in retirement then you are doing the right thing.
By that I mean most people do not even get around to thinking about it.
This is probably the most important stage of planning for an income in retirement. If you are still saving and investing towards retirement then the best thing you can do is to sit down and work out what you want to do when you no longer have to work. You may wish to carry on working, but it will be your choice.
Think of the things you want want to do in a typical year in retirement. Write them down and then put some costings against them. Now you have an idea of what it will cost you to retire. Now you can start to think about how much you will need to be able to retire. If you know this you can start to plan properly to save and invest towards retirement.
What you invest in is entirely up to you and it may be worth a chat with an adviser to explore your options.
If you are already retired then you will have built up the assets you need to be able to retire. Now it is your job to maintain those assets to ensure their value keeps pace with inflation at least. This will help to ensure the income they generate keeps pace with inflation so that you can continue to afford your current lifestyle in the future.
Again it will depend on what assets you have to generate this retirement income for you but it can always be worthwhile speaking to someone to check you are making the best use of your money.