为什么.env文件优先于环境变量的.yaml文件？

Question

What is/are the main reason(s), for which Symfony preferres to use .env files - for holding values of environment variables in them - instead of using the more flexible .yaml files?

I am asking this, because I read this comment, which states:

It was much simpler when we were using .yaml file.
I totally understand why we needed to switch to .env file, [...]

Thank you for your time.

Answer 1

According to a Symfony blog post:

Their main advantages are that they can be changed between deploys without changing any code and that they don't need to be checked into the code repository.

The same cannot be said about yaml files.

https://symfony.com/blog/new-in-symfony-3-2-runtime-environment-variables