Hot leads are users who filled out an application, added a product to the cart, and left a phone number. In short, hot leads are the people who show their interest in the product, they are ready to buy. Cold leads are users who have encountered an advertisement for the first time and know nothing about the product. When they open the landing page, they read for the first time that there is a company called “Comfortable Chairs” that will make them custom-made chairs.