First thing’s first, if you think you don’t need a rod holder and you’re perfectly find holding the rod yourself, that’s fine. But the holder isn’t just to give your hands a break. These tools are especially useful when you’re trolling.
The holder holds your rod in place while you focus on operating the boat, making notes, or checking the electronics. The holders can also help you from getting tired from holding your rod for hours on end.
The rod holder can also allow you to use more than one rod (evenly spaced so the lines don’t get entwined with one another) at once, thus improving your chances of getting a catch.