What are the consequences of failing to comply with PCI DSS?

The consequences of failing to comply with PCI DSS primarily involve financial and operational risks, which aligns closely with the correct answer. Non-compliance often results in significant potential fines imposed by card brands or banks, which can escalate based on the severity and duration of the violations. Additionally, businesses may experience increased transaction fees due to their risk profile, resulting from inadequate security measures to protect cardholder data. This lack of compliance can also elevate the risk of data breaches, leading to possible financial losses, damage to the brand's reputation, and further compliance costs associated with recovering from such incidents.

While other consequences mentioned may seem relevant, they do not capture the primary legal and financial implications of non-compliance as effectively. For instance, while operational challenges like increased training requirements or lower transaction speeds can occur, they do not directly reflect the primary and immediate consequences of failing to meet PCI DSS standards. Immediate revocation of merchant licenses is also not a standardized outcome, as revocation typically follows more systemic compliance failures or repeated infractions, rather than being an immediate consequence of a single instance of non-compliance.