Reputational damage is often intangible, subjective, and hard to quantify, making it the most challenging aspect to measure.

“Reputation impact is difficult to quantify and may have long-term effects that are not immediately apparent.”

— CISM Review Manual 15th Edition, Chapter 4: Incident Management, Section: Post-incident Analysis*

ISACA practice questions highlight that reputational damage is uniquely challenging to measure accurately.