Whether or not you need to go to graduate school completely depends on what type of field you'd like to go into, but for some it's required like:
- physicians assistant
Some fields very strongly recommend a graduate degree and it can be difficult to reach one's full potential in the industry without it:
- Business management (MBA highly recommended)
In many other fields it's nice to have a graduate degree and many specific positions highly encourage it, but it's certainly not mandatory to get a job. Many people work for awhile in an industry to get some experience and then get a masters degree or doctorate in that field, or perhaps in a totally different field if they want to start something new. It will likely never hurt you to have a graduate degree, but it can be a very timely and expensive investment, so make sure it's worth it for the career path you want to take before investing in one.