I am a Salesforce consultant for multiple clients, and we have different scenarios wherein the Salesforce Sales Cloud has been used. Use cases include different scenarios and different industries, so from banking to automobile industries, to NGOs, nonprofits too.
One use case is for a client in the automobile industry. There is a sales process, sales funnel, that has been built for the particular company, according to the region. When there is a lead that comes into Salesforce, according to the region, they will be assigned to a particular salesperson. If the lead is converted, then an opportunity has been created and the opportunity is nurtured through Salesforce. There are different tasks that will then be allotted to the particular salesperson in each opportunity stage.