I think it's ironic that one of the most corrupt country in the world happens to be very religious.... I'm talking about Nigeria of course.

It would seem very confusing at first, until you consider the fact that there is a high rate of poverty. And with poverty comes desperation, a longing for comfort, need to deal with stress, a sense of purpose. And one tool that meets this (sadly) is religion.

The thinking pattern becomes
- Don't worry about your poor hard life on Earth because when you die you get mansions in heaven.
- Keep praying, and paying tithes so that someday god would bless you and make you rich, pray to cast and bind your enemies.
- God is there to provide for you things government can't; protection, health, finances etc.

This belief is why religion is very prevalent in Nigeria, and many other countries with hardship and a failing government, conversely imagine being born in say Canada or Australia, these needs are more or less met by the high standards of living.

The thinking pattern becomes
- A good government and economy would provide you a good standard of living, why long to die and go to heaven when you're doing fine here
- Success isn't due to God and failure isn't due to enemy forces, it's all due to forces that we can control.
- Why need god when government can meet your basic needs; good healthcare, adequate security, job availability ..etc.

In such thriving nations the need for religion wanes out, thus we expect to see less religiosity. (There are few exceptions though, but the trend is still there).

https://www.csmonitor.com/USA/USA-Update/2015/0316/Do-countries-become-less-religious-as-they-get-richer