Maintaining a good standard of living after retirement can be difficult. Not only is the income usually lower than it used to be, but taxes can also become a burden.

An analysis by Key concluded that almost 14% of the yearly income in retired households is lost to taxes. Many people may not realize that income tax may still need to be paid after retirement.
This applies to all income above the personal allowance. A personal allowance is an amount you can earn without being taxed. Currently, you do not have to pay tax if you have received less than or up to £12,570. Unfortunately, even the State Pension is taxed.
Not only is income tax something to think about, but also council tax can be expensive. Research by Key Retirement Solutions shows that income tax and council tax can reduce the average income in a retired household by 13.9%.
Source: https://www.entrepreneurshipsecret.com/standard-of-living/