End users(aka your product managers) care about developer efficiency. Let use the article on this post. When you have a large code base with lots of unit tes

End users(aka your product managers) care about developer efficiency. Let use the article on this post. When you have a large code base with lots of unit tests. You want the ability to parallelize tests so it doesn't have an hour to run all the units tests. That wait time will kill developer efficiency. Waiting to see if your code will break build and also having integration tests take over hour will guarantee that you will have broken code in source code repository because devs won't wait an hour to run units tests locally and just will merge stuff especially EOD Friday.