This is a question that I am working through today as I look at a short-list of opportunities in front of me. I think the answer depends on the type of business you want to have as well as your ultimate long-term goals.
Here are just a few of the things that we are considering:
a) Do you intend to be privately held or is their some larger plan?
b) Do you want a product or service-based business?
c) Will you self-fund or raise capital or both?
d) What is your exit plan, if you have one?
On the Market
a) Could you be a first mover?
b) If not a first mover, how many players are in the market today?
c) Is there a clear leader in the space?
d) Are those players meeting market need sufficiently? (untapped market potential)
e) Is the market big enough to sustain more than one successful company or is it winner takes all?
f) Is the market stale with lack of innovation? (Jobster saw that in recruiting)
g) Who are the buyers of your product/service - how do they buy? (sales cycle time, type of sales approach required, etc.)
h) Have you interviewed at least 10-15 potential customers in the market to understand their needs and their perspective? (if not, Do not pass go - go straight to jail - do not collect your $200)
There are more. Perhaps when I get further down the path I will publish the ideas that didn't "make the cut" and why.