Would suggest that depends on each inventors personal goals, experience and situation in life. I personally like bringing my ideas to market - I like being responsible for their success. Others, who don't know where to start in launching products may be better either licensing or finding someone to do it with. If the goal is purely making money then Licensing might be the way to go but I would have some concerns about how to protect my idea and make sure I don't put in loads of work only to have the potential licensing company take my idea.
So - long story short - depends what inventors want and their personal goals etc.
---Andrew PS - Here's a free report on creating your startup success. Free report
For those who watch Dragons' Den (Canada), the investors usually tell the entrepreneur that licensing is the way to go. They believe it's much better than bringing the product to the market yourself and building inventory at the same time. With licensing, it'll allow you to bring your product to an already established company and collect royalty fees.
So what are your thoughts on this? Do you believe there's room to manufacture and sell the product on your own, or should one just license and open checks every month?