I am majoring in Finance and think knowing German would be useful in the business world and also am interested in knowing German. Would this be a waste of time? Would I truly know German fluently after minoring in it?
I don’t think it’s a waste of time if you are interested in it. I may be biased because I love learning languages and I have also studied a bit of German.
Now would you really be able to speak German fluently after minoring in it?
You definitely will have a good grasp of German. In the beginner and intermediate level, a lot of professors are very nice (at least the ones at my school and the neighboring schools) and you can easily pass without being able to converse that well. However, in the higher level, you will have classmates who can speak very well. So once you get to the higher level (which you will if you are minoring) and you want to be able to keep up with your overachieving classmates, you have to put in more effort. And that effort will allow you to be more fluent.
A tip for you, though: you are going to have to put in a lot of time outside of class to be able to speak fluently. The teacher will guide you with what to study, but it’s your job to practice the language in your own time. But yes, it is possible to be fluent.
Maybe if you do a semester abroad you will pick up more German.
Definitely go to Germany - as often as possible. You may never actually use German in a business context, because so many people will be using English. However, you may want to take a job in Germany, and would enjoy life so much more with the language. Also, there might be a business need to learn a more obscure language, or a language from a part of the world where business English is not as common. Then you will need the language learning skills that you acquired while having some fun with German. Who knows? It may even become more common to do business in German internationally. Languages rarely go to waste.
And if you do go to Germany, insist that they speak to you in German. They will immediately want to practice their English (unless you are at a bank or government office ;-))
I spent 3 years in Germany so I know.