Under most circumstances, the WCAG level most commonly set as the minimum goal is:

The most commonly set minimum goal for web accessibility under the Web Content Accessibility Guidelines (WCAG) is Level AA. This level contains a comprehensive set of criteria designed to ensure accessibility for a wider range of users, including those with disabilities. Level AA addresses essential accessibility issues by incorporating requirements for visual presentation, audio content, and navigability, among other aspects, making it practical for a majority of websites and applications.

Level A, on the other hand, represents the basic accessibility requirements. While it is important, it may not sufficiently cover the broader user experience for people with various disabilities. Level AAA sets the highest standards and contains additional criteria that can be quite challenging for many websites to implement, making it less feasible as a standard minimum goal. Thus, Level AA strikes a balance by offering a solid foundation for accessibility while remaining attainable for most organizations.