Security is not treated as a separate concern from software quality, maintainability, or reliability.

Poor maintainability often increases security risk.

Complex systems are harder to:

• review
• validate
• audit
• maintain securely

Simple and explicit designs are generally safer.

Systems and users should only have the access they actually require.

Examples:

• avoid administrator execution when unnecessary
• restrict exposed interfaces
• minimize credential scope

No single security mechanism should be treated as perfect.

Multiple independent protections reduce risk.

Security-relevant decisions and vulnerabilities should be:

• documented
• reviewable
• reproducible

Security decisions should reflect realistic environments and operational constraints.

Industrial and test systems often have different threat profiles than internet-facing cloud systems.