Direct calls allow developers to communicate with an API by sending standard internet protocol commands, but this method requires specifying every parameter explicitly and can be complicated to troubleshoot, making it less preferred for many developers. On the other hand, SDKs abstract away the minutiae of the API, providing a more straightforward way to access the service using a programming language framework, offering simplicity and speedier development, but requiring resources to develop and maintain. While both methods have their advantages and disadvantages, most developers prefer SDKs due to their ease of use, streamlined functionalities, and ability to handle complicated authentication procedures, making them the preferred method for interacting with APIs in many cases.