Why create digital marketing campaigns?

We can understand that digital marketing is dedicated to promoting consumption for example; of technology resources.

When a user has bought a high-end phone that meets his expectations, he suddenly finds an ad about the same company with the latest version of the device, but now with a triple camera; Without ever having a need to change phones, the user is now thinking hey should have that latest version! The user is not dedicated to photography at an expert level but would like to share his moments with excellent shots on social networks.

It may be thought that marketing is generating needs that somehow promote the attraction of customers to purchase a product or service, however marketing also gives answers to users, you cannot generate or innovate a product without first knowing what it demands the client, for this, market surveys are carried out with which precise results are obtained about what the client expects from the brands and they serve to know if we are correctly applying our marketing strategies.