I honestly don't get the value of this tool. If I already have a parametrized set of Terraform scripts for creating an environment, what is stopping me from sp

I honestly don't get the value of this tool. If I already have a parametrized set of Terraform scripts for creating an environment, what is stopping me from spinning up and tearing down my own ephemeral environments in my CI pipeline? This is what we're doing today and it works pretty well. What is this tool actually providing? I feel like there's something fundamental I'm misunderstanding.