I think this is the best definition I’ve seen so far of that elusive term “product sense”:

I define great product sense as the ability to do two things without having extensive data (i.e. without running lengthy research upfront):

• Generate many solid, highly profitable ideas for ways to make money
• Intuit whether a product is likely to be successful with a high degree of confidence

The detail of having this sense without extensive data is important. Anyone can get to a great product via guess-and-check. The best product minds reliably take a more direct path.