If a person's patent is still in progress should he put his product in the market?

If the patent is filed and is pending, then it is protected, but it can’t be licensed.

I think @ghaz0001 is asking more of an advice question – should he do it, and not a legal question.

My answer is YES – make some money on it. I have seen the words “Patent Pending” on dozens of products over the years. You’re legally the owner of the idea once you apply for the patent, unless it isn’t approved.