No one writes code and ships it to production before testing it works.
It's just that most Developers test their code manually.
They write the code, switch to a browser or terminal, and run it.
It might be a quick task, such as reloading a page or executing a command, or it could be complex and time-consuming, such as filling in a long form and checking the results.
In this case, automated testing is a good option.
Instead of filling in the form, have the tests do it for you.
It will be quicker and more reliable than doing it manually.
