Apple has strict guidelines for its App Store review process, which can lead to delayed reviews or rejections if an app fails to meet these guidelines. The standard review time is less than 24 hours, but this may be longer if the app requires human review. Common reasons for delays include unfinished or buggy apps, inadequate review information, incomplete or misleading metadata, and privacy violations. To avoid these issues, developers should ensure their apps are complete, provide accurate information, and follow Apple's guidelines on metadata and privacy. In case of delayed reviews or rejections, developers can request expedited reviews, reach out to the App Review team, or use CI/CD tools like Bitrise to simplify the deployment process.