there is something to be said about working in a company first
There is no doubt a handful of entrepreneurs who have been at some type of business or another since they were able to walk and that is a unique breed. They have an innate understanding on how to grow a business and understand when the business needs to be tweaked. Yet there are also many entrepreneurs who are stubborn and refuse to do it any other way but their own. When you have a group of investors that care about the success of the business too, I'd recommend rethinking that type of behavior but it just sometimes comes with the territory.
I see (and so do all investors) so many business ideas these days. Some of them IMHO are awful while others are interesting yet I can't imagine how they can make any significant amount of money to create a need for investors. Regardless many of the people behind these start-ups have never really had a job in a start-up but are just jumping into the start-up game.
One investor I know is frustrated with first time entrepreneurs who really have not learned on someone elses dime. The beauty of working in a start-up before starting your own is that you get to see in person what works, what doesn't, what the realities are of growing a business from scratch. The ability to wear a bunch of different hats...and more than anything an education in how hard it is to build a business and to see first hand what works and what doesn't work can only be a tremendous value for anyone moving forward in their career.
I certainly applaud everyone who is starting their own businesses. I write about that often and as far as I am concerned the more entrepreneurs the better. Yet there is something about learning the underpinnings of a start-up business before embarking on your own. I also believe that working with a team can teach you about your own limitations including your best assets. That is helpful to know before starting your own as you know what makes sense in a partner.
Bottom line...there is something to be said about working in a company when you get out of college or even graduate school before immediately jumping into your own start-up. The road is long and the more you know before embarking on your own endeavor it might be worth learning a few things of value before going down that road.