A validation survey is a tool for gaining insights into whether customers will be disappointed if your product goes away or if they will refer other customers. It is generally very simple, with closed-ended feedback responding to a single question. You can also apply it to other types of assumptions you wish to validate with your customers, such as customer satisfaction, consumer effort score, and brand awareness.   Another popular type of validation survey is validating the importance ranking of the jobs, pains, and gains in your Customer Profile in the Value Proposition Canvas. Most teams take their best guess at this ranking in a workshop setting but need to quickly get feedback from outside the building to see how close they are to the real world. You can easily do this in most survey software today by creating two boxes, one for the list and next to it one for the customer ranking.   One type of survey is called the Sean Ellis Test, which is named after its creator and growth-hacking expert Sean Ellis. His approach is to gauge desirability through scarcity. The Sean Ellis Test keys in on one important question: “How disappointed would you be if you could no longer use this product? Very disappointed, somewhat disappointed, or not disappointed?” It can be argued that you’ve not achieved [[product-market fit]] until a score of 40% is reached.