Indirect costs are supporting expenses that are harder to tie to a single tool, system, or incident. In cyber security, they include ongoing monitoring, alert triage, patch coordination, user training, maintenance, audit work, and the staff time needed to keep defenses running. These costs often do not appear in a purchase order, but they shape the real price of a security program.
They matter because a control can look cheap until its hidden overhead is counted. For example, a logging platform may require tuning to reduce false positives, and an incident may trigger extra coordination, recovery, and business disruption. Attackers also create indirect costs when they force defenders to spend time on investigation instead of normal operations. Good security budgeting and risk analysis should include both direct and indirect costs, or the organization will underestimate total exposure and overstate return on investment.