Eli5: Why does the OECD exist?



I know only three things about the OECD:
1) It’s a policy-making body
2) Member countries aren’t required to implement OECD policies
3) The member countries have high GDPs

But, I don’t know:
1) Why the OECD exists in the first place. Why would a country spend money doing research to come up with policies that the country may not even want to implement? Why wouldn’t they just fund their own (domestic) policy research to come up with policies that they actually do want to implement?
2) How often do the OECD member countries (and specifically, the U.S.) implement OECD policies as their own law?

Can anyone help me understand this? Thank you!

In: Economics

If the OECD had binding policies, no one would want to join, or they would at least have serious reservations about joining. Making them voluntary recommendations makes membership much more palatable.

As for why join, two heads think better than one. While each country is unique, there are generally broad similarities that each country shares with some others. Aggregating and analyzing this data in a group can help find different relationships that might not be apparent. Also, even if member countries are different now, one may want to develop more similarly to another. Being part of the same “think tank” and being able to see some of their role model’s policy/data can be helpful in this regard.