What's the idea behind managing a secret in a key vault via Terraform?

There is the possibility of managing a secret in a key vault via Terraform:https://registry.terraform.io/providers/hashicorp/azurerm/latest/docs/resources/key_vault_secret

resource "azurerm_key_vault_secret" "example" {  name         = "secret-sauce"  value        = "szechuan"  key_vault_id = azurerm_key_vault.example.id}

However then the secret szechuan would need to be commited to Git, and I was wondering what's the idea or use case behind using this Terraform resource? Should it for example be stored in a variable, but then from where would the value for the variable come from (without committing it to Git)?