There are many theoretical approaches to retirement funding. If you ask a 50-60 year old their strategy, you will get a very different answer than to ask a 30 year old FIRE (Financial Independence Retire Early) person about their strategy. Much has to do with willingness to take on risk. I investigate these different approaches and why both are fundamentally flawed and present a simple answer that I have used successfully.
This information is primarily for US persons, but may apply to you. Check out the full details here:
https://www.beunconstrained.com/article/details/mastering-the-challenge-of-retirement
Enjoy!