You need to be able to hold the violin so that it won’t slip out and fall on the floor!
That would not be so good. 🙂
You want to find a way to hold it so that you are comfortable enough and not creating extra tension. Too much tension can cause injury if you are practicing for hours, so if you can begin with a semi-comfortable position, you will do better from the start.
Here are some people who show how they hold the violin: