Many businesses are missing a big opportunity by not finding the right time to make incremental sales. 

Or you could call it situational selling. In the right situation, you offer an additional service or product to the customer. 

It is what we do in the hotel and restaurant business. We encouraged it and sometimes would create a friendly competition. 

Some people call it upselling, but it is more like upserving because you are finding a small way to serve the customer even better. 

At Disney World, guests will listen when a cast member makes a suggestion. If you use the situation to sell additional services or products that will help a customer, you are not serving them well. 

If I visit your store to buy a shirt and also come out with three ties, you served me well because now I have the exact ties to look good in my shirt. It saves me the trouble of looking for the proper tie later. 

Incremental sales through situational selling will add a boost to your bottom line. All those little additional sales add up. If only 10% of the people say yes to your offer it adds up to big sales over time.