It's not that simple. First you can't always choose the stack you work with. You work with other people, who may have expertise in different languages. You may

It's not that simple. First you can't always choose the stack you work with. You work with other people, who may have expertise in different languages. You may have to reuse existing code written in different languages. And it's rarely the case that some stack is better than another on every aspects, there is usually some form of compromises to be made.