Salespeople are often told to never take no for an answer.  If you follow that advice, however, you're setting yourself up to sell less rather than more.  Here's why.

1. Some people simply aren't going to buy.

"Never take no for an answer" assumes that  making the sale is just a matter of asking for the sale in a different way.  However, there will always be people who are not going to buy, regardless of what you say or do.  These people self-identify themselves by saying "no" early in the engagement.

2. Some people will buy but cost too much to sell.

Some prospects that will eventually buy end up taking so long to decide, and asking you to do so much for them, that it's not worth your time and effort selling to them. Like the prospects who aren't going to buy, these prospects self-identify by saying "no..." early in the engagement but adding a condition that delays the sale.

3. Persistence costs you money.

A good salesperson quickly weeds out poor prospects and focuses on real opportunities that create the maximum revenue with the minimum of overhead.  Here's good advice: if first you don't succeed (i.e. you get a big "no"), try, try again... but with a different prospect.

In short, NO means NO.  Why fight against reality?  Accept the no and move on.